Sunday, December 19, 2010

Santa's approaching!

It is that time of the year again – Santa is New Zealand-bound as I write, relatives galore are streaming back to their hometowns, and in all the fuss about the festive season, the poor old garden is likely to be overlooked.
Flowers play a large part in the way we celebrate the season though, with some plants intrinsically intertwined into the season, including the heavily scented Christmas lily, Lilum regale.   This Chinese species always has a place in our garden, although my family did not have a tradition of using them.  The Head Gardener’s family, on the other hand, coveted them dearly and some of our original stock came from her grandmother’s garden.   We were given some other bulbs when we shifted here and these plants turned out to be giants - at over two metres tall they were twice the size of the other forms we grow.  I decided it might be environmental and grew some from seed of the tall ones - and they are just as tall, so I have two strains here, each distinct.
They do, of course, have some things in common, including trumpet shaped flowers, wine-coloured on the outside as the trumpet expands, then pearly-white inside, with a marked golden throat.  The anthers carry bright orange pollen, which stains the inside of the flower on wet days, and the clothes of those careless when picking them.  And of course they share that magnificent heady perfume.  I find it a little oppressive when the flowers are picked for the house, but love it in the garden when the white flowers shine in the evening air.
Another plant we associate with Christmas is a cultivated relative of the milkweed that is currently a curse in our new vegetable garden.  The wede species I am referring to is the little yellow-green flowered annual, Euphorbia peplus.  This is a common weed of cultivated ground, easily removed, but the milky sap is a skin irritant and many a gardener has cursed after accidentally getting some of the sap on their lips.  Smoking gardeners beware!
The poinsettia is a widely grown pot plant, a Mexican relative of milkweed, and has the same milky sap, but the flowers are altogether more exciting.  The varieties that we are most familiar with have bright red bracts – the flowers are small and insignificant in the middle of these modified leaves – but there are also pink, white and cream varieties around, as well as combinations of these.
If looked after, poinsettias will be long-lived house plants.  They need a good amount of light but should be kept out of direct sunlight as sun can scorch the leaves. They prefer a warm and well-lit room so should be kept near a sunny window, or on a table in the middle of a sunny room. They should definitely be kept out of cool breezes, as they can be sensitive to the cold.
If you want to keep your plant happy and healthy it is very important to get the watering right – poinsettias like to be kept damp, but resent being over wet. Use the finger test – if the soil is moist the slightly spongy then the plant will be fine, but if it feels dry you should water until water flows freely out the bottom of the pot.  Do not sit the pot in a puddle of water though - you are better the sit the pot in a sink until the water has stopped flowing out of the bottom before putting it back. There is no hard and fast rule about when to water – just use your common sense and check it every few days. 

Sunday, November 28, 2010

Mountain laurel

I was wandering around my local garden centre the other day and saw the most amazing display of that exquisite American shrub, Kalmia latifolia, with a wide range of varieties on display in full flower.  This is one of those shrubs that has never attained the degree of popularity it deserves, and if you are looking for a small to medium sized evergreen shrub which flowers in early summer you could not do better than this wonderful species.
Commonly called Mountain Laurel in its native country, it is a member of the vast Ericaceous tribe.  It is found from Maine down to northern Florida and extends westwards as far as Indiana and Louisiana.  
Unsurprisingly for a member of the same family as heaths and rhododendrons, it is usually found on soils with a very low pH – about 4.5 to 5.5. is the norm – and like rhododendrons, is toxic to most stock. Some related species are known as “sheep kill” so it gives you a good idea of the danger of planting this beauty along a fence line on a farm!  You might also want to avoid major plantings if you are a hay fever sufferer, as the pollen is said to be a bad irritant, although it flowers as the same time as so many grasses that I do not think you would notice it unless you popped your nose into the flowers.
In the wild Kalmias have rounded clusters of beautiful light pink to white flowers, each dotted with a little “stitch” where the stamen have been pushing against the inside of the petals – it is sometimes called the Calico Bush.  Even the buds are very attractive, crimped and pointed like little buttons of icing on top of a sweet cake.
To be grown very well the Kalmia needs to be placed in well-drained but moisture retentive soil, preferably with low pH.  It can cope with light shade but it is equally happy at home in full sun.  As it flowers late in the season the flowers are not usually prone to frost damage and it can be relied on for a glorious flowering season.
About ten years ago I was determined to grow one here although our soil conditions are not really ideal.  I found a fairly sheltered spot and dug bag after bag of compost into the soil before purchasing a well-grown specimen from a Rotorua nursery. It has flourished and each year at this time I marvel at how well it has done, and how much it flourishes.
But when I see the great range of colours available now, I feel cheated, and I have to say I am scanning around the garden to see where I could make some room for a new shrub or two of these beauties.
Among the varieties that took my eye the other day, ‘Carousel’ was probably the pick.  This is an American bred cultivar, from the extensive planned crosses by the doyen of Kalmia breeders Richard Jaynes. It has light pink buds, and flowers that are light pink but dominated by the bands of cinnamon red.  The effect is off a brightly banded bouquet of flowers. It is relatively slow growing and should not be more than 1.5 metres high and across by the end of ten years.
I was also taken with the brightly flowered ‘Minuet’, a smaller growing variety with large flowers.   The light pink buds open to dark pink flowers with a light pink centre and bands of bright cinnamon red.  This variety, which is smaller growing as the name indicates, also bears unique, dark green narrow leaves.  This is another of Richard Jaynes’ varieties.
‘Yankee Doddle’ is another stunning type. The buds of this cultivar are bright red-pink and they open to show a pink corolla with a narrow maroon band, giving the effect of a strawberry parfait.  Despite its very American sounding name, this cultivar was actually bred in Germany, where Kalmias are very popular garden plants. 

Sunday, November 21, 2010


Let’s face it – we live on the eastern side of the country’s main mountain ranges and the weather comes from the west.  That means we live in a rain shadow and that little fact should act as a guide as to what we plant in our gardens – but of course, it doesn’t! 
If we live in a dry zone where we should be planting Mediterranean and Australian shrubs, we naturally want to construct gardens out of rhododendrons and hostas, while those gardeners who inhabit wetter regions like Taranaki yearn to grow bearded irises, lavenders and sun-loving plants.  It is just human nature to be contrarian I guess.
I do not grow huge numbers of hostas but I do have a row of healthy specimens filling up a long thin south-facing bed along the front of house.  The bed was so narrow I could not think of anything else that would cope with the peculiar conditions that a cool but dry situation offered.  They have flourished and steadily increased to such as extent that I can divide the plants up every few years and take small colonies to plant in other parts of the garden.
The best of these plants is a delightful blue foliaged form I grew from seed about twenty years ago.  A friend had an extensive country garden and wanted to bulk up some areas in shade with mass plantings of hostas.  The garden was on a large sheep station tot he eats of Masterton, and the gardener’s wife was a very tolerant man – he had to be as the home paddocks kept disappearing into the garden! – but his acceptance of the expanding garden did not stretch to buying hundreds of hostas as about $10 each. 
As we were discussing the problem she said she had lots of need on her plants, so I asked her to bring some in and we sowed them into big seed boxes, and eventually pricked out many hundreds of plants, none of the named varieties of course, but many of them perfectly fine for the garden, and some quite pretty forms.
I gave my friend hundreds of plants, but still had plenty to grow of for myself, best of which were the blue ones, which resembled the popular H. sieboldiana ‘Glauca’ perhaps the best known of the older blue forms. Blue varieties are very much in fashion at the moment being the best selling forms, sometimes with a golden variegation.   If you like large leaved forms then ‘Big Daddy’ is probably as good as any, but if you would prefer a smaller form for the edge of the border, ‘Hadspen Blue’ is  lovely little plant with the most gorgeous blue-green foliage with summer spikes of pale lavender flowers above the foliage.
I am not absolutely sure but I think one of my other forms is the old favourite ‘Thomas Hogg’, also known as Hosta undulata ‘Albo marginata’.  This variety with green leaves edged with a bright white margin and was supposedly introduced to western horticulture by the New York nurseryman Thomas Hogg in 1875.  Hogg, who was a great fan of hostas, or Funkias as they were then known, had spent a lot of time in Japan, seeking out new varieties for his nursery.  This old variety does not have the strong foliage of more modern hybrids, and as such is a little prone to slug attacks, but it is reliably hardy and will even cope with more or less full sun as long as the soil is not too thin and does not dry out too much.

Tuesday, November 16, 2010

Getting under cover

The spring appears to have almost missed our inland valley and we have rushed headlong from winter into summer.  We seem to have traversed from cool, sunless days into gloriously shining days bereft of rain.  The lawns, always a good indicator of how the season is going, have been sluggish this year, not having their usual mid-spring burst, and they are now looking suspiciously as though they are starting to dry off.
What it all means is anyone’s guess – are we in for a sustained drought this year, or are the anticyclones going to head south, leaving us with a muggy, La Nina summer, with plenty of rain?  I guess only time will tell.
Plenty of first time vegetable gardeners will be looking with interest at their new plots, wondering what else they can plant, and asking themselves what they should be doing.  Well, watering is a good place to start.  It is not going to be long before most towns and cities start their annual water restrictions, so it is a good time to get things prepared by ensuring all plots are well watered, and all soil is well covered.  If you have bare soil (as I have in the old vegetable garden) make sure you get something into it, or onto it.  If you are planting, get it done before the real dry weather arrives and then apply a generous mulch of some kind.  In the vegetable garden a compost or straw mulch is very beneficial, helping keep the weeds down as well as keeping soil moisture contained, and it works just as well in the flower garden.
If you have planted small fruits or tomatoes for the first time, don’t forget to cover them from the depredations of birds.  I do not mind the occasional fruit being sacrificed to help keep the local avifauna alive, but I do object to the feathered fiends figuring they are entitled to strip all my crops.  They have already found the new strawberry bed and took the first few fruits before I realised what they were up to.  Of course, I had to shift the old strawberry bed away from the swimming pool at the same time as I relocated the vegetable garden, and the old cover does not fit the new bed, so I had a rushed job after work one night, hastily putting a new cover with plastic bird netting over it.
The raspberry canes will have to be covered too as they have set a nice crop.  I cover them each year and manage to keep the birds at bay – now I just have to figure how to stop the light-fingered little girls from taking the bulk of the crop.
Tomatoes are more of a problem, one I have really only had for the past few years.  I think it started with a bumper crop of Sweet 100 a few years ago, but once the birds had learnt to take the little brightening fruit they just swapped over to pecking away at all the crop.  I have had to resort to covering all the plants once the fruit start to lighten, but I resent it!  I use the white netting that you see on grapevines later in the season, and peg them to the stakes.  It works alright.
Others gardeners have an even worse problem, and find that their leaf crops are being attacked.  We have had this problem in the past, especially with young plants grown from seed, and I found the best answer was to make little cloches out of chicken wire, easily movable, and I just covered the young plants with them until they were established.    You could also try the time honoured technique of stringing defunct CDs on pieces of wire.  The reflections from the discs as they spin in the breeze is said to freak the birds out and they desist.

Monday, October 25, 2010


The little girls next door are world experts in “pink”- it is their favourite colour and it is not unusual to see them dressed in pink from head to toe, riding pink bikes.  I tease them, telling them I hate pink things.  I have not told them that pinks, Dianthus species and hybrids, are in fact among my favourite plants.  I cannot tell them now, or all my complaints about their colour will be ruined!
It has made me think about some other plants that have given their names to colours, in particular the lilacs and lavenders that are now in flower.
Of the two, lavenders are by far the more popular, but at one time lilacs were among the most planted of shrubs.  I guess their deciduous nature is now counting against them, as most modern gardeners are intent on creating gardens composed entirely of evergreens, but they are fabulous spring flowering plants. 
Botanically the 20 or so species of lilac glory in the name Syringa – brings unfortunate word associations with visits to the doctor does it not? – although in old books you might see that name attributed to mock oranges, Philadelphus.  If you hunt around you can probably find a few of the less common species, but in the garden centres you are most likely to come across forms of the common lilac, S. vulgaris.
I was staggered to see that there are about 1500 different hybrids and varieties available worldwide.  There is certainly nothing like that number around New Zealand – you would probably be lucky to find twenty or so varieties in most nurseries.  These are mainly older hybrids, and funnily enough, not very many of them are actually lilac coloured.  Perhaps the best of those that are actually ‘lilac’, is’ Madam F Morel’, a single flowered, fragrant pinkish-lilac.  ‘Alice Eastwood’ is a double flowered form with similar colouring, although it has a more spreading habit of growth.
I am not sure which “non-lilac” variety is my favourite.  I like ‘Charles Joly’, another older form but in this case with very deep reddish purple flowers, but I also like ‘Mme Lemoine’, a lovely white flowered form which seems to have lighter green foliage than most hybrids.
One of the most interesting forms is ‘Sensation’, which has rich purple single flowers with each petal edged with white and carried  in large semi-open panicles produced freely on a medium to tall shrub. This one is well worth seeking out.
If you are looking for something with a finer, lighter feel than the old lilac varieties you should keep an eye out for Syringa 'Bellicent’, an upright deciduous shrub which bears fragrant pink in panicles in late spring and early summer.  These are carried over dark green foliage often with light variegations. It is hardy and well suited to a shrub border or as a specimen.
Lilacs are not too fussy as to their growing conditions.  They certainly prefer a well-drained soil and a position in the sun or light shade. It is best if the soil is neutral to a slightly limey as lilacs grow very poorly in acid soils and heavy clay. For good flower production a moist soil, full of well-rotted compost or farmyard manure is recommended. In recent years New Zealand has discovered an export market for these flowers, and numbers of growers are slowly increasing.

Sunday, October 17, 2010

It is Labour Weekend and that means we are all going to be exhorted to get into the garden centre and spend, spend, spend on our summer vegetable gardens.  In our cooler climes I think it pays to wait for a week or two before planting the most summery of crops, but I do not know about this year.  Even though it has not been very sunny, we have had a mild spring, with next to no frosts.  Even when we have had a southerly outbreak, we have dodged the icy bullet by having easterlies with their attendant clouds.
So, let’s just go ahead this year and get planting tomatoes, peppers and the like this weekend – or maybe next. 
This is all predicated on the soil being ready to receive the plants.  If you are a traditional dirt patch sort of gardener (as opposed to the newer “raised bed filled with potting mix” sort) you should have already worked your soil up, by adding some compost and fertiliser.  
 I have a slight problem this year.  As you will be aware we have had to dig a new garden, and I have made about half of it out of soil from the recycling centre.  This will have been made largely out of a mix of clippings from the local recycling centre and some treated soil, but the clippings present a threat.  They will almost certainly include some week-killed grass clippings and some plants, including tomatoes, absolutely hate even a trace of these chemicals.  I will have to take care to make sure I put the plants into the old soil.
I have already worked some fertiliser into the soil, but I will also add some dolomite to help keep the nutriment balance right and will add some slow release general fertiliser to the soil when I plant, as I know I am unlikely to remember to give the plants the amount of side dressings they ideally need. The next step is to put the stakes in place.  You do not want to wait until the tomatoes are already planted as you will damages the young roots as you hammer the stakes into place.
I am assuming you have not saved your own seed, and are going to have to buy some plants in from the nursery.  If you have been growing F1 hybrid plants (and I think you should be) then you cannot save your own seed as they will not come true to type.  If you have been growing an open pollinated variety you could have saved the seed last autumn, and have sown about a month ago, but it is probably a bit late now.
You will probably find a slightly bewildering array of plants on offer, with old favourites like ‘Moneymaker’ and ‘Grosse Lisse’ available, as well as a wide range of both heritage types and more modern hybrids.  Personally I think you should go for modern F1 hybrids for the bulk of your plants.  I know many people believe they are not as flavoursome as the old types, but I think that is a misapprehension based on supermarket fruit, which are picked before they are properly ripe.  Grow a modern type like ‘Taupo’ and you will never go back to the older ones.
Among the good modern ‘Moneymaker’ types you could look out for are ‘Taupo’, ‘Hamlet’ and ‘Better Boy’, while larger fruited types include ‘Better Boy’, ‘Big Boy’ and ‘Big Beef’.  If you are a fan of Italian types you will probably prefer the old fashioned ‘Italiano’, which I think is as good as any, but you might struggle to find that. ‘Roma’ and ‘San Mazarno’ are two good modern types.

Sunday, October 03, 2010


I had a phone call from a friend the other day telling me that his wisteria was about to flower and asking if I would like to call and see it in a few days.  I was glad of the call as he and his wife have one of the most interesting plantings in front of a very appealing 1920s bungalow.  A wisteria is wound across the top of a verandah, underplanted with a pair of majestic weeping standard roses which grow above a mix of green and purple weeping maples, the whole bed edged with a clean row of box.  The overall effect is very sophisticated and looks attractive all year round, but it looks at its best right now.
The wisterias are Northern Hemisphere climbers, mainly from Asia but also with one or two species from America.  The ones we grow in the garden are almost without fail the Asian ones, especially the Japanese W. floribunda and the Chinese W. sinensis, both of which are firm favourite s with gardeners the world over.
The various forms of the Chinese wisteria are the most commonly grown forms.  It a very vigorous deciduous climber which can get to an enormous size if left unchecked and in spring has long racemes of lilac or mauve flowers, always heavy with a heady scent.  It flowers in the middle of spring with a big burst of fragrance before the leaves appear and always gives a dramatic show.
These climbers are usually grown in the way my friend has grown his plant – as climbers that twine their way across wires, pergolas and trellises, or sneak along fences, but they can be kept as handsome shrubs – even as weeping standards.  I have a friend who even has a small example in a large bonsai pot and the effect is amazing.
The most commonly available variety now is W. sinensis ‘Caroline’ which has fragrant lilac flowers.  This is a real weather tamer, seeming to flower through the worst of the nor-westers without being shredded, and also coping with the rain without marking too badly.   She will usually throw a second crop of flowers in summer – a lot smaller crop of slightly pinker flowers.
The other named varieties you are likely to come across are more likely to be from the Japanese species W. floribunda, and are almost certain to have longer racemes.  The longest of all are from the variety called ‘Macrobotys’, which has blue/purple racemes of pea-shaped flowers that can be as long as a metre, although in their home country plants have produced racemes as long as 1.8 metres!  The long racemes give a longer flowering season too as the flowers open from the base, slowly working their way along to the tip. Obviously, this plant needs to be trained high enough to take account for its long clusters of flowers.
There are the usual lilac coloured forms of this species too, ‘Cascade’ and ‘Lavender Lace’ perhaps being the best known,  but it  has also given rise to a wonderful range of coloured varieties as well.   W. floribunda ‘Alba’ and ‘Snow Showers’ are delightful white varieties, as their names suggest.  They both flower at about the same time as the new leaves open, but as the leaves are bright lime green the effect is appealing enough. 
At the opposite end of the colour range is the intriguing but somewhat misnamed ‘Black Dragon’ – do not expect to get jet black flowers.  In this case the flowers are actually very dark purple in the bud, but they open to deep violet.  The flowers are unusually doubled (the only variety I have ever seen that are) and very fragrant, so they are well worth having.
If you are like the little girls that live next door to our garden, you will be delighted to know  there are some pink forms too!  With both the varieties ‘Lipstick’ and ‘Pink Ice’ the buds are pinker than the flowers, but the light coloured flowers definitely have a pink cast.

Sunday, September 19, 2010

It has been another wet week, but it has been an interesting one for me.  An old gardening friend called in to see me with a potted daffodil bulb, wondering what variety it was.  It was a small cupped variety and the petals seemed a very unusual colour – sulphurous green/yellow, with deeper green infusions.  It has me quite flummoxed so I took it up to see another gardening mentor who has a passion for dwarf daffodils.
She thought it was probably the variety known as ‘Yellow Cheerfulness’, saying it was variable in colour depending on where it is grown, and that it would probably go more yellow as it opened up.
I have never grown ‘Yellow Cheerfulness’ despite growing most of the common members of that tribe of narcissus, and knew it mainly from selling it for many years, always in packets that show it as bright gold.  Turns out the packets were very misleading – it is actually light yellow, fading to almost primrose, and does sometimes take on a decided greenish cast, depending on exactly where it is grown as soil conditions can alter the flower colour.  It does, however, have a delightful scent – less heady than ‘Cheerfulness’- and I will hunt it out next autumn for my garden.
That little matter disposed of, we took a walk around my friend’s extensive garden, and she clipped little flowers from her many treasures for me to bring home in a couple of delightful tussie mussies, featuring all sorts of precious little bulbs and perennials.  But funnily enough, it is the rhododendrons that I am enjoying most now, including a couple of un-rhododendron-like looking species.
My friend has a small glasshouse in which she grows all sorts of interesting plants, including one of the most oddly named rhododendrons – R.. goodenoughii.  This is a lovely species of from the Vireya section, hailing from Goodenough Island in Papua New Guinea, a dramatic species with large fragrant white flowers held above large deep green leaves.  The Waitara nurseryman Mark Jury likes this plant, saying it was not “nearenoughii” when he was first given this splendid but rare species.  He clearly liked “wellenoughii” though, as he grew it commercially for a number of years!
Vireya Rhododendrons come from the subtropical and tropical areas of the world, and are best known for their dramatically colourful flowers.  In the wild they tend to grow in the tops of trees, in a big pile of leaf litter, although there are also some terrestrial species as well.
As you can imagine, they are easier to grow in the milder areas of New Zealand, but even in cooler areas such as ours, they can easily be accommodated by being grown in unheated glasshouse, or even in patio areas.  They prefer cooler conditions over summer, so need to be kept shaded and well watered.

Sunday, September 12, 2010


This has been a remarkable season for deciduous magnolias – the best I can remember in years. We have gone through a sustained period without any strong frosts and that has meant that the buds, so often cleaned out by the cold weather, have been able to mature into full blooms, and have been spectacular.

Among those to look their best this year have been the various forms of Magnolia campbellii, with their stunning pink flowers, and the amazing white M. denudata ‘Alba’. There are not too many of these trees in our inland location, partly I guess because the flowers are so frost tender that it can be a heartbreaking occupation growing these beauties. They are also very reluctant to flower early in their lives – we always used to tell people it could take up to 15 years before they would settle into flowering.

If you want to play it safe there are always the very hardy old forms of M. x soulangeana, which are reliably hardy although they are perhaps not as entrancing as modern hybrids, tending to be thinner, tulip-shaped, and often rosy purple flowered. These are the giant magnolias that grace most suburbs in established New Zealand towns. We don’t have any in our garden, but in our neighbourhood there are trees nearly 20 metres high, and they are covered with flowers at this time of the year.

As they grow they take a very pronounced rounded form, which looks slightly eerie over winter (some kids call them witches trees!) but come the spring, when covered with their multitude of two-toned flowers, they are just amazing.

The newer hybrids are a great advance, and over the past fifty years or so, New Zealand has led the world in producing M. campbellii derived hybrids in an amazing range of colours, with increased hardiness and more precocious flowering, as well as reduced size.

The initiator of this progress was Felix Jury, one of the well-known plant breeding family from Taranaki. He had ordered a plant of the M. campbellii form called ‘Lanarth’ from England, but when it first flowered it was immediately obvious that it had been sent in error and was not true to type, but was nonetheless very attractive so he released it, calling it ‘Mark Jury’ after his son.

But things did not stop there. He used this as a parent, crossing it to more compact forms, and developed a wonderful collection of hybrids, including the enormously flowered pink form, ‘Atlas’, the lovely two-toned ‘Athene’, the delectable pink ‘Serene’, two stunning white forms, ‘Lotus’ and ‘Milky Away’, and the remarkable creamy pink ‘Iolanthe’, with its long lasting flowers.

‘Iolanthe’ flowers young, with giant saucer shaped creamy pink flowers that are borne along the branch, not just at the tip as is the common way, meaning the flowering season lasts longer than most other varieties.

Sunday, August 22, 2010

I had a bad case of déjà vu the other day.  I was wondering through my local garden centre having a look through their new arrivals, when I noticed a lovely red Leucadendron, with bright shining bracts.  It looked a little like the old variety we used to sell as L. salignum ‘Red’, so I looked closer to see what variety it was.
I was pleasantly surprised to see it was named ’Jack Harre’, after the well known and regarded protea grower.  It brought back pleasant memories of trips up to the Harre nursery at Rewa, near Kimbolton, where we would load up truckloads of Leucadendrons, Leucospermums and Proteas, and then retire for a cup of tea with Jack.  He was an ex-dairy farmer and his nursery was not the tidiest one you will ever see, but he certainly knew his plants and had a great way with words.  He wrote a very good book on the Protea family, and was even interviewed by National Radio about his childhood.
The Leucadendron named for him is a compact growing form with flaming-red star-like bracts at the end of arm-length branches from early in winter. The cooler the weather becomes, the deeper the flowers become.  This is a rapid growing form suitable for most gardens, and becomes a nicely rounded shrub. 

Sunday, August 15, 2010

Pebble gardens

During this past week I have been corresponding with a Christchurch-based researcher who is writing a history of New Zealand gardening.  He was interested in the changing way we have gardened over the past forty years, the time I have been active as a gardener, nurseryman and garden writer.
It made me think of the huge changes made in the garden world, with the demise and diminution of many of the specialist flower societies that were once so popular – who has a cactus club in their region any more? – and to the many fads that have come and gone during that time.
The writer was especially interested in the cult of the pebble garden in the 1970s, wondering whether it really was as popular as some of the literature of the time would indicate. 
I can certainly recall the intense interest in this form of gardening, which seemed to involve me unloading truckload after truckload of bags filled with dirty and heavy scoria, the pebble of choice, even this far away from the source, and the thousands of dwarf conifers and small Ericas that were very much in fashion for these gardens.
I suspect the fad came from a combination of the popularity of the Western American Sunset series of garden publications, which stressed the idea of planting gardens that required little maintenance, combined with the English notion of heather gardens, largely comprised of Ericas, Callunas and dwarf conifers.
In New Zealand we added some native elements – the variegated Hebe ‘Waireka’ seemed to be in every pebble garden, along with the yellow flax, Phormium ‘Yellow Wave’, and the dwarf  dark leaved kohuhu, Pittosporum ‘Tom Thumb’.
The craze did not last very long, but in a way it has a continuing influence, with many modern gardens having stone mulches and, especially in northern areas, a Californian planting style.
In our rush to get away from such plantings we have also abandoned many of the plants that were such a feature of ‘pebble gardens’, and maybe it is time to rethink our attitudes to these once-popular garden features.
I recently stopped and looked at a heather bed in the Wellington Botanical Gardens, and I was underwhelmed.  It contained a number of cultivars from both the Northern Hemisphere, generally with smaller flowers in clusters that flower in winter and spring, and those from the African continent, which have larger flowers, a greater colour range, and also flower for a longer period.  I think most of the plants would work be of more value when planted in a mixed planting, and should not be isolated in a ghetto of Erica-only beds.
For winter flowering it is hard to go past Erica melanthera, especially the form sold as ‘Improved’, which has a vibrant mass of pink haze from early June, and the exciting  Erica ‘Surprise’, a supposedly pure white form of Erica melanthera which sometimes produces both pink and white flowers hence the name.

Sunday, August 08, 2010

The weekend did not start very well for my whangai granddaughter.  A soccer game in the cold and wet went gone badly awry, the scoreline being so onesided I will not embarrass her by repeating it here, but let me assure you, it was ugly, and made worse by her having friends playing in the opposing side.
To try and rescue the day, we decided we would take her younger sister and investigate the pig pens and chicken coops at the nearby school to revive flagging spirits.  Fortunately the rain had abated and the wind had died down, so we traipsed across the paddocks to see our farm animal friends.
The children were enchanted by the ham and egg production units, but I was far more taken with the wildlife – mud-encrusted pigs’ snouts just do not do it for me, but the sound of the tuis chortling and singing away in the adjacent gum tress was a delight.
The school has a major planting of gums for firewood but the tuis were inhabiting a beautiful specimen of the winter flowering red gum, Eucalyptus leucoxylon ‘Rosea’.   This is a selected form of a widespread Australian species, with deeper coloured red flowers than are normally found in the wild and is an invaluable tree for the gardener wanting to attract extra bird life into the garden in winter, as it flowers for many months during the coldest time of the year.
It is a small to medium sized tree (among a family that has some giant members) with attractive light-coloured bark and typically olive green gum leaves and, although it probably grows too big for small gardens, it is one that should be considered for slightly bigger sections.
I know those who advocate all native gardens for everyone are not going to like the idea of planting Australian gums tui feed, and they are not going to like the idea of using Banskia integrifolia for the same reason. It is perhaps not the most exciting of this Australian genus of trees and shrubs, but the light yellow bottlebrush flowers, usually with a funny greenish cast as well, are very freely produced through most of winter. 
There are many different varieties of this species in Australia, including both coastal and mountain forms with different growing requirements. The most commonly planted forms in New Zealand are all seed raised and seem to be able to cope with most anything our climate throws at them, although they do struggle with cold and frosty sites.
It is hardy and quick growing, and is often used for shelter belts in warmer areas of the country.  It copes with both sandy and clay-based soils, so is a good choice to help establish new gardens.

Sunday, July 11, 2010

A new beginning

The weekend was freezing cold again – but this time I was happy enough with the cooler temperatures, as I had to dig out a new garden, or rather extend an older one. 
It was all a bit annoying actually.  A visit from the swimming pool inspection team resulted in the information the pool had failed because we had a vegetable garden in the same enclosed area. The kindly inspector patiently explained to me why it was a bad idea, and I have to say I grudgingly agreed with him, although I am still perplexed as to why the pool had passed previous inspections.
I accepted the inevitable, and tried to think of ways around the problem, in the end coming to the conclusion that I had to transfer my vegetable garden out of the enclosed area and into an adjacent area at the end of the driveway.  The cleared vegetable grounds would be converted for flowers and shrubs.
That entailed one slight problem.  The garden bed at the end of the drive was not big enough, and I knew would be in for a few hours of strenuous digging to convert old driveway into garden.  I had created the original bed in the January of the first year we were here, and I knew how hard the compacted base mix was going to be, but I also knew there was going to be some well drained soil underneath it, and I would be able to create a well-drained and fertile garden.
It was certainly easier digging in the cool of winter – the first time I dug this compacted tangle of sandy spoil and small boulders in the summer heat I was taking a break every fifteen minutes and diving into the pool!  This time I started in the frosty cold, and as the day warmed (slightly) and I heated, I discarded layer after layer of unwanted clothing until I ended up in a tee shirt and shorts.
As I worked I recalled the interesting plants we had grown in the border over the years.
The bed started out as a mixed border, with lots of perennials and annuals to keep it colourful.  The first year of planting featured some annual and perennial Lavateras.  The perennial ‘Barnsley’ was undoubtedly the star of the garden.  This is the delightful light pink tree mallow that seemed to be in everyone’s garden in the early 1990s, and is a sport from the deeper pink form called ‘Rosea’.  It is a quick growing, floriferous plant, flowering for months over spring and summer, but it tends to be short lived.  It is easily kept growing from cuttings and certainly makes a wonderful display if grown in the sun with good drainage.  Keep an eye out for reversions to the deeper form – it is not quite as attractive.

Sunday, June 27, 2010

I was looking through some of my gardening books on Saturday, as I recuperated from a period outside in that awful windy and wet weather. As often happens, I did not find what I was looking for, and, as usual, it was my own fault – I got sidetracked by a remarkable coincidence.   Two different books on perennials described themselves as being the definitive one, “from Acanthus to Zauschneria.”
What is interesting is that both these name are probably unfamiliar to anything other than keen gardeners, although one of them is, or rather was, quite a common plant.
The most famous of the many species of Acanthus is the plant known to generations of gardeners as ‘Bears Breeches’, A. mollis.   This is a handsome perennial with shining, green leaves whose distinctive cut shape is replicated in architectural decoration, most famously atop Corinthian columns.  As well as a good show of luxuriant looking foliage, the plant carries a wonderful flower show – spikes of purple bracts that enclose white flowers, up to 1.8 metres high.
This plant is at its best in light shade, with good shelter and a deep moist soil but it can be a bit invasive, spreading by deeply buried rhizomes, and, once established, is tricky to remove entirely.  It is a valuable plant for the edge of woodland or in semi-wild areas, but perhaps not one to introduce into the most valuable spaces in the garden.
There is an interesting golden foliaged form around, originating in the Hollard garden at Kaponga in Taranaki, called ‘Hollards Gold’.  It is very attractive but is just about as persistent.
The only other species sometimes seen in New Zealand is a prickly customer, as it the name A. spinosus suggests.  In contrast to the above, it has lanceolate leaves, heavily dissected almost to the midrid, and also carries a smattering of soft spines.  Unlike the above, this prefers full sun and a well-drained soil, and is often seen with other spiky sunlovers, such as agaves and aloes.
The other end of the alphabet, the Zauschneria is not as popular as it should be in New Zealand, as it is a bright and cheerful perennial with a lot going for it.  As its common name of ‘Californian Fuchsia’ suggests, it is a native of western North America, and it forms a dense bush from a woody rootstock.  The grey/green foliage is topped through the summer and into the autumn with brilliant scarlet flowers, tubular in shape, reminiscent of fuchsias.
This is an easily grown plant in full sun and well-drained soils, where it will easily grow about 40 cm across and about 50 cm high.  There is a white form around, which is pretty enough in its own way, but the red is the thing with this plant, so get that one if you can find it.  It can be increased by division over the winter, but it strikes readily from semi-softwood cuttings in the spring and I think that is the easier way to go.
Another California perennial that is seldom seen is the amazing Californian Tree Poppy, Romney coulteri, which has the most glorious semi-transparent delicately crinkled white flowers,  about 150 mm across.   I guess it is best described as a sub-shrub, as it does form a sort of woody base, growing to about 1.5 metres high and around that wide too, but it best treated as though it is an herbaceous perennial, and cut back each year.
The foliage is grey-green again, very deeply cut,  and the flowers are borne in clusters of up to 20 on the end of long stems which branch at the top.  These flowers, which can be cut for the house although they have an unusual fruity scent, are carried through the spring and into the summer.
This plant is very particular about where it will grow.  It needs good drainage and full sun – it simply will not do well in the shade or damp – but then it presents another problem.  If it likes where it is growing it can grow too well, and be a bit of a pest.  It spreads with runners from its fleshy roots (root cuttings are the best way to increase it) and in well-drained sandy soils it can be a bit of a pest.

Sunday, June 20, 2010

From my office window at home I get a nice view of my neighbour’s golden totara, which is one of those trees that are interesting year round.  In the spring the new foliage makes the whole tree go bright green, but as summer arrives it turns rich yellow before arriving at the deep golden colour it keeps for the winter.  If left untrimmed at makes an attractive irregular growth habit, but of you have a passion for clipping it can also be kept well under control and trimmed to whatever height you want – within reason.   I have seen it used for hedging and the effect is spectacular.
The golden totara, officially Podocarpus totara ‘Aurea’, is a male form and as such will grow slower than most seed grown trees, and will grow in most soils, but like many totaras, does not like to have wet feet.
I think this lovely golden totara may be one of our most underrated trees as it provides some colour, without being a glaring as most of the golden forms of other conifers, such as Macracarpas.
There are not that many golden trees than can comfortably be planted into a modern-sized garden.  When I first started in the gardening trade we used to sell hundreds of golden elms, Ulmus procera ‘Lutescens’ also known as Louis van Houtte, but as this quickly tunrs into a giant,it is too big for small gardens, despite its attractions.   In spring, the new leaves are bright golden- lime but as summer moves on they age to soft golden yellow, deepening to rich yellow in autumn.
It is one of the hardiest golden leafed trees, well able to cope with windy exposed sites. A friend grew some along the top of a rise on his farm, exposed to winds from all quarters, and, although the trees were certainly not as luxuriant as they would have been in a more sheltered spot, they also grew perfectly well for him.
Probably the most popular golden tree for home gardens now is the wonderfully bright Robinia pseudoacacia ‘Robinia’.  This is not really a naturally small tree and needs the occasional pruning to keep it under control, but there is no doubt it is a wonderful tree.  The Robinias are native to the United States and Mexico, R. pseudoacacia being the only species commonly grown.  The type species is a very fast growing tree which has a suckering habit, making it used for erosion control at one time – the stock would not eat it and the timber is very durable, even when untreated.  Having said that, it is hardly a tree for the home garden, as it easily reaches 15 metres in ten years, and does not stop then!
‘Frisia’ was, as the name suggests, discovered in a Dutch nursery, and during the 1980s became one of the most widely planted trees in New Zealand.  It forms a tidy head of bright golden foliage atop a sturdy trunk, and is manageable with a little care.
Pruning is made slightly more difficult because of two traits of most Robinias – prickly stems and hard but brittle wood.  Because the wood is also so hard, a saw is usually better than pruning shears, other than with small branches, and even then, because the stems are also brittle, they sometimes snap before the saw is halfway through, so be careful.
‘Frisia’ can be pruned almost any time of the year, even during the periods of high growth, but be warned that if you cut it back too heavily it will respond with very rapidly growing new shoots which will need careful pruning within a month or two.

Sunday, June 06, 2010

Red Hot Pokers

The problem of the winter garden is tackled different ways in different parts of the world. For much of the world that suffers a continental climate, the garden is wrapped up and put away for the winter. There are so few things that can cope with snowdrifts and biting cold that people who live in such climates do not expect to have anything in flower. They pull their garden inside, to ledges in their kitchens, or shelves in their conservatories, and they hibernate until the weather is a little more kind to their gardening aspirations.

In warmer parts of the world the exact opposite happens. Winter is the cooler season when plants can be grown, so gardeners approach the winter season with enthusiasm. In some parts, the summer weather is so hot and dry that plants have evolved reversed deciduous pattern – they go leafless over the summer. In other places, the summer is so wet and disease-ridden that many cool climate crops rot, and have to be sown over the cooler, drier winter period.

Then there are those of us who garden in temperate zones, who like to think we do not have bad winters, and expect our gardens to be at their best all winter long. We plant seedlings that are grown for spring display in other parts of the world – polyanthus and Primula malacoides for example – to give us colour through the winter, and we even look to some perennials to give us colour through the cooler months.

Among those we can rely on are some winter-flowering members of genera we normally think of as spring flowering, and probably the best known of those is the long familiar “Winter Cheer” Red Hot Poker. This is the stoutly performing orange-red flowering plant that is seen in many city gardens (and seemingly every country garden) from the top of the North Island to near the bottom of the South. It can be relied upon to flower from as early as June through to spring.

This is such a tough and free-growing plant that we tend to take the other members of the vast Kniphofia genus for granted, but there are some wonderfully valuable garden plants among them that deserve to be better known.

“Winter Gold” is a case in point. This is probably the best of the golden flowered forms, growing to about 1.2 meters, the same as ‘Winter Cheer’, but this time with golden flowers that start out limey green in the bud.

These two fulfil another function as well. Each flower head is actually a cluster of small tubular flowers which (usually) hang down from the long stems. These small hanging flowers are filled with nectar and over the winter they will be visited by birds, feeding on the nectar.

Overseas these plants are usually called ‘Torch Lilies’ rather than ‘Red Hot Pokers’ and that avoids the clumsy construction that we Kiwis get ourselves into when we want to talk about the other coloured varieties of Kniphofia. For example, it is faintly ridiculous to talk of a yellow ‘Red Hot Poker’, but that is what we are forced to do!

Although New Zealanders are most familiar with the tall growing forms of these South African beauties, it is in fact among the smaller flowered forms that we find the most attractive range of subtle colours. I grow a number of these dwarf varieties and they provide lots of interest in the summer and autumn garden.

Sunday, May 30, 2010


For beginning gardeners, the idea of planting roses in the depths of winter sounds a bit crazy, and for many of us older gardeners, the thought of mainly planting them in the flowering season seems like an equally insane idea! 
I can recall when container grown roses first appeared on the market, and the lack of enthusiasm that garden centre staff had for the idea, thinking it a silly fad that would not catch on.  We were wrong of course, and the rose planting season has long ago extended to cover most of the year.
I must be old fashioned but really believe it is better for most deciduous plants to be shifted during their dormant season, while they are at rest and can better cope with the surprise to the system that transplanting imposes on them.  Rose planting is easy at this time of the year, provided a few easy preparatory steps have been taken.
The first step is to decide where the roses are to be planted.    As a rule, they do best in new soil, so if you are planting into an area that has already had roses in it, it pays to remove the soil and replace it.  This is due to an insidious disease called “rose sickness” which, although it does not normally kill roses, makes them grow in such an unhealthy manner as to make them ungardenworthy.  If you are replacing soil in an existing bed you will need about a wheel barrowful of soil for each plant.
If you have the luxury of creating a new bed, make sure it is in full sun.  There are a few (very few) roses that will cope with semi-shade, but most will need the maximum amount of sunshine, to help keep them disease free if for no other reason.  Those that will do better in the slight shade are those whose flowers tend to get burnt in the full sun.
Soil type is important too.  The best soil for roses is undoubtedly a slightly stiff loam.  By that I mean a good garden soil that is not too light, as thin, sandy soils will dry out too much over summer, and the roses will fail to thrive.
If you have anything other than very rich loam, it pays to work in some compost or well-rotted farmyard manure.  Ideally, this should have been done about a month ago, but if you have not had a chance to do it, it is still fine to do it now as long as the manure is not green.  It is a good idea to try and keep the bed at the same level as the surrounding ground as elevating the bed will just make it drain more quickly, giving problems late in the dry summer period.

Sunday, May 23, 2010

Autumn foliage

This is surely one of the interesting times of the year, with a plethora of wonderfully coloured trees and shrubs to look for in the streetscape. I wonder how long this will last however, as the heyday of planting deciduous trees seems to have long gone, and as more and more gardeners plant almost only evergreens, we are going to miss out on such a grand autumn display.

One of the reasons for the diminished use of deciduous trees and shrubs is surely the more diminutive gardens we now have. We simple do not have the space for the same number of large specimens and are more reliant on smaller plants for the garden.

Some plants that will fit easily into most gardens, and can be reliably called upon for a spectacular display are the various members of the Cotinus family. These are the Smoke Bushes and feature some of the most amazingly lurid colours in the autumn palette.

There are three species of these in the wild, but there are only two that are commonly available. The first of these is the European smoke bush, C. coggygria which actually grows from Europe into central China, and is perhaps best known for the large panicles of fuzzy looking plumes in early summer that give the plant its common name, especially as they grey into the autumn.

The leaves are bright green during the bulk of the growing season, but as they autumn approaches they take on the most startling array of colours, from yellow to orange to fiery red. They appear to differ from plant to plant, suggesting the New Zealand forms have been seed raised, as overseas, varieties can be selected for a particular colour.

The exception to this rule is the strongly coloured ‘Royal Purple’ which has deep wine-purple leaves which have a conspicuous waxy surface that appears translucent in sunlight. The flowers are a slightly deeper colour through the growing season, and then turn bright orange and burning red in autumn. This is a great plant for associating with lighter coloured foliage. At slightly more than two metres high it is about two thirds the height of its plainer cousin.

The American species C. obovatus is a taller beast altogether, growing to perhaps five metres. It does not have the same floral display of its European kin, but makes up for that with a stunning foliage display in the autumn, when the leaves turn yellow, orange, red, purple – often all at the same time – to give an very impressive show.

In the very small garden, there is another little treasure that can be relied upon to give a great display in autumn – and it is not even deciduous. The dwarf heavenly bamboo (do not worry it is not actually a bamboo, so it will not go mad in the garden) Nandina domestica ‘Pygmaea’ was planted extensively during the 1970s craze for pebble gardens, and has perhaps not regained its proper place in the garden, but its fresh lime leaves during the summer always look attractive, and in autumn and winter it turns on a very impressive display of purple, orange and (more usually) bright red foliage. The colder the winter, and the poorer your soil, the better this will colour up. In fact, you could even do the old nurseryman’s trick of feeding it a bit of sulphate of potash at this time of the year – it will certainly colour up better then!

Saturday, May 15, 2010

Shining examples

When we select new plants for our garden we go through a sort of checklist.  We will include all sorts of different attributes for consideration as we think about our garden – flower colour, foliage colour, foliage shape, maybe even foliage texture – but we seldom think of how well the foliage reflects light. 
It might sound like a slightly daft thing to be weighing up when choosing plants, but it does have quite a bearing on how we perceive the plant in the garden, especially in winter when light levels are lower.  A plant that has a soft surface, covered with fine hairs for example, will absorb much of the light it receives, giving a soft reflection.  On the other hand, plants with highly glossy leaves will reflect back much of the light, giving them a brighter appearance.
Perhaps the greatest examples of the power of reflection –“shining examples” I call them – among native plants are the many Coprosma species and varieties.
There are over 100 species in the genus, distributed through the Pacific Rim but centred on New Zealand, where about half the species are found.  Many are dwarf shrubs with tiny leaves, but there are also some small trees to be found among the species.
Until recently the best known plant was undoubtedly, C. repens.  This is a soft-wooded shrub that will grow as a prostrate shrub in exposed conditions, but in sheltered and humus-rich sites can grow up to nearly ten metres.  It has dark green, very glossy leaves, earning it the common name of Looking Glass Bush, Mirror Plant, New Zealand Laurel or Shiny Leaf.  I am sure you get the idea!
What has made it very popular as a garden plant is the wide range of coloured sports it has given rise to, which has meant it has become a very popular garden plant in coastal areas in particular.  Unfortunately, its reliable performance in windy and exposed sites is matched by its tenacity at setting seed, and it has escaped from the garden in parts of Australia where it is now classed a weed. Perhaps that just our revenge for the magpie!
Over the past few years a lot of coloured hybrid coprosmas have been released onto the market, with so many options for the gardener that it is a little confusing.  A trip to the garden centre and a stroll down the “dwarf natives” section will certainly be a colourful experience, especially at this time of the year when so many of the cultivars colour up.
‘Lemon and Lime’ is a small leaved form with very interesting variegation of green and yellow.  As the cooler weather appears, the yellow deepens and hints of orange appear.  This is a tidy growing form, and like almost all of these hybrids, it is very disease resistant. It is the child of an even better variety – one that has become one of the best selling shrubs in New Zealand, the unremittingly cheerful ‘Evening Glow.’  This has golden foliage over the summer but as autumn arrives it takes on rich orange and deep red hues.  That is not a bad achievement for an evergreen shrub, and it has made it into one of the most popular natives.

Sunday, May 09, 2010

Autumn glories

The balmy autumn has continued, much to the consternation of many farmers and gardeners. Warm and sunny days, and near frost-free conditions might be nice of you are on holiday or looking to relax, but it is starting to be a nightmare again for those who need some rain. The summer was moist enough to keep most east coast farmers happy, but there will be a few out there scratching their heads, wondering what happened to the autumn rainfalls. The same applies to gardeners – a weekend in the garden has shown me it is much drier than I had thought, and as I finished each section of the garden, I dragged a hose behind me to try and get some moisture into the soil.

As always, we will be looking at the bright side, thinking that a relatively calm autumn might be good for autumn colour, but the warm conditions will militate against that too, as warmer temperature actually lead to less colour. Has anyone ever travelled to Auckland to see the autumn display?

I caught the start of the autumn colour season while in Dunedin recently. High on hills at the northern end of town, the Dunedin Botanic Garden is a treasure for garden lovers, filled with all sorts of exotic treasures, set in well-tended gardens that I wandered through on a number of occasions. Near the end of our stay, I took my camera with me for a concerted walk through as many of the different gardens as I could.

I was not expecting the Rhododendron garden to be as interesting as it was, bearing in mind it was so late in the season. There was very little in flower, although there were some R. yakushimanum varieties flowering out of season, but the effects of the coloured foliage, a mix of maples and azaleas mainly, was outstanding.

These plants are both relatively easy to grow, and can usually be called on to give a good year-round display.

The deciduous azaleas are probably best known for their wonderful display of flowers in late spring – October and November – when their delicious red, yellow and orange displays are so eye-catching. They flower on bare wood (usually see later) so the flowers are displayed very prominently, and being late flowering they are also safe from frost.

These very hardy plants are probably not as popular as they once were, but they give an unrivalled display, and they are very garden friendly. They are hardy, pest free, easy to look after, and very long lived – what more could you look for in a shrub?

Botanically, these plants are Rhododendrons, and as such need a relatively acid soil, preferably also moist. They are shallow rooting, and they do need to be kept moist over the summer, so thin limey soil is not for them.

There are many varieties on the market and it is pointless for me to suggest any particular ones, but the New Zealand raised Ilam hybrids seem as good as any to me. If you are in the Manawatu area in spring, a visit to the Rhododendron gardens at Kimbolton will be enough to make a convert of you.

Sunday, May 02, 2010

Edges and hedges

One of the difficult areas of the garden is the border lands – those awkward areas where the garden finishes and other elements of the environment start.  It can be the line between the garden and the lawn that is the problem, or perhaps the delineation between physical boundaries, such as neighbouring properties or a driveway or roadway.
In some situations an informal edging between the two environments works well.  In a woodland garden, for example, it looks great of the understory of planting gradually give way to a soft bark pathway, or even on the edge of quite hard planting, the effect can be softened by having sprawling plants that help blur the edge.  We have a wooden wall retaining an elevated lawn area, and have planted some trailing plants to help soften the boundaries.  Sometimes, though, you actually want a clear delineation between two different areas, and that is when formal hedging some into it own.
 I was recently in the extensive gardens of Larnach Castle, high on the Otago Peninsular, overlooking Otago Harbour and Port Chalmers – I was supposed to be visiting the castle itself, but the gardens held my attention for much longer than the building.  Even though it was late autumn and the garden was long past its summer splendour, there was still plenty of interest.
The formal gardens in front of the house have been cleverly designed to reflect and augment the severe Scottish Baronial architectural style employed in the castle, with very formal edgings in somewhat informally shaped beds.  The beds are extensively edged in box, with corner highlights of totara topiary.
There are a number of varieties if box hedging, all forms of Buxus.  The most commonly grown is English box, a relatively slow growing form.  This sounds like a less desirable trait, but you have basic conflict between the desire to have your edging looking as mature as possible, as quickly as possible, and the need to keep the growth under control once the plant has reached its desired height and width.
I would plump for English box, perhaps buying the more expensive advanced grade plants, which can be found easily enough in the trade. They will be four years old and perhaps 40 cm high.  Pop some fertiliser in the soil once the plants are well established, and continue to fertilise about twice a year.  It is essential to water the fertiliser in well as it will burn the foliage is just left sprinkled on the surface.

Sunday, April 25, 2010

Little berried treasures

A recent trip to the South Island had many highlights, but one of the was an early Sunday morning stroll through the Christchurch Botanic Garden, looking and photographing the many horticultural treasures the garden contains. 
I spent some time conversing with another early morning riser in the Curator’s House vegetable patch.  He was, he delighted in telling me, a European, although he seemed to me to have a perfectly New Zealand accent.
His origin was a talking point as we discussed the flavour of the little New Zealand cranberries, Myrtus ugni, that were heavily in fruit.  He pinched a few of the bright red berries and chomped on them enthusiastically.  He said he was puzzled that I did not share his predilection for this Chilean native.
For those of you not familiar with this little shrub, it is a small growing evergreen shrub from South America, with small glossy dark green leaves that are spicy if crushed. In spring they bear small drooping white flowers which are followed by small pink to red fruit, which can be born from March to May.  They have a very peculiar fragrance and taste – something sweet surely, but underlain by a turpentine flavour. 
My fellow visitor insisted that I was displaying my British origins, and if I was European I would love the flavour, as the more sophisticated European palate prefers the slightly turpentine flavour of the berry.  I cannot say I was convinced, but being a basically affable sort of guy I agreed with him, and we happily went our separate ways.
The clever gardeners had used the cranberries as a hedge at the edge of the vegetable plot because it forms an easily trimmed barrier that can be kept relatively short, and will also not rob the garden of too much nutriment. This smart little plant will also look good as a part of a shrubbery, and I have even seen it used an espalier and as a subject for topiary.

Sunday, April 18, 2010

Christchurch plants

I was standing at the counter in my local supermarket when a lady came up to me, asking me to identify a plant she had seen on a garden tour.  She did not have it with her and could only give a vague description – it was a perennial with blue flowers and did not grow very tall.  I was very confused at first, but then she gave me the crucial piece of information – the flowers were sort of everlasting.
I knew then what it was – but it took a bit of head scratching before I finally managed to dig the name out of the dark recesses of my mind – Limonium perezii.  It is not a plant I had seen for a few years, but at one time it was very popular.
In the late eighties there was a bit of a passion for growing everlasting flowers for the market, and lots of small paddocks were planted with row upon row of everlasting daisies and annual statice plants.  The fad did not last very long and the paddocks were returned to ponies, or perhaps upgraded to alpacas.
But the craze did engender a bit of interest in some of the more unusual members of the statice, including this intriguing plant, so I was intrigued to see clumps of this Canary Island native in a perennial border in a recent visit to the Christchurch Botanic Garden on a recent visit.
The border stretched along a long stretch from the museum entrance down towards the hot house, and featured a great range of cool climate perennials, as well as a few warmer ones.  It was long past its best, with lots of dead flower heads on view, but it still had lots of interest.
Limonium perezii is sometimes called Prez’s sea lavender, and is one of many valuable garden plants from the Canary Islands.  It has a woody rhizome, from which tough bright green leaves about 30 cm long, emerge, followed by a stiff panicle of flowers.  The flowers are small, with purple sepals and white petals, but they are carried exuberantly.  They look fine on their own, but even better when grown in clumps.  They associate well with other Mediterranean plants like lavender, rosemary and bearded irises.
As a matter of interest, these have slightly naturalised themselves in warm parts of California.  I do not think they would be a problem here, but I also know they are relatively easy to grow from seed, as I have done it!
There are many species in this genus but not that many worth growing in the garden.  The very best is almost impossible to buy in New Zealand – the wonderful pink flowered shrubby South African species I knew as L. roseum, but now called L. peregrinum. This grows to about two metres and with bright green leaves.  It is covered with panicles of pink flowers, which fade as they age.  It is very difficult to grow and not even easy to propagate, but it is a thing of rare beauty.  I grew some from seed gathered from a friend’s plant and was able to sell them all very quickly.

Monday, April 05, 2010

All the way from Amsterdam

When I say I have a mania for tulips I do not want you to get the idea that I have caught the obscure Dutch disease of the 17th century and mortgaged the house, sold the car, traded in the Head Gardener and bought sacks filled to the brim with tulip bulbs.  Because things really did get that extreme in Holland at one time. The rarest of the varieties sold for 10 times the annual salary of a tradesman.  Assuming you plumber makes about $60,000 a year, that is $600,000 for one bulb!
Now I am mad about bulbs, and I love tulips, but that amount of money almost beggars belief.  And of course, it was not about the bulbs at all – the whole sensation was perhaps the first economic bubble.  As long as more and more money kept chasing less and less bulbs, the price was forced up, and up, until it all fell down in a heap.  Remind you of anything that has happened recently, with finance companies and house prices?
Still, we can count ourselves lucky because we can buy bulbs at a severely discounted price to 1637, and can afford to splash out and buy enough of these bulbs to make a solid effect.
Normally, I would be against the idea of bulk planting bulbs.  The flowering season is too short and if you get bad weather in the middle of that season, you miss out on a whole year’s worth of blooms.  But I am prepared to make an exception for tulips.  The effect of the massed plantings in the Wellington Botanical Gardens is genuinely amazing – even our non-gardening son was impressed with the display and wandered around taking photographs.
Tulips are relatively easy to grow and flower, for the first year at least.  They will have been grown in ideal conditions over the previous growing season, and the flower will have been formed and lock in deep within the bulbs.  All you need to do is provide it the right conditions and it will sprout forth for you next spring.
There are a few little tricks to bear in mind.  In our conditions it pays to plant tulip bulbs a little later in the season that most other bulbs.  They need a proper period of chilling before they will bloom properly, so it pays to buy pre-chilled bulbs, or to hold off planting until the season is a little cooler.  For warmer areas you can even plant into June, but I would think you would be best to get your bulbs in by the end of this month, or perhaps into early May.