Monday, January 25, 2010

At last - the true Geraniums

For the past couple of weeks we have been taking a look at the plants most gardeners call “geraniums”, although they are in fact members of the closely related Pelargonium genus. These are the showy succulent perennials, largely from South Africa, that grace most New Zealand gardens, usually placed in dry, sheltered areas where other most plants struggle.

There are however, many very useful plants among the true Geraniums, and they are met with much more infrequently, despite being colourful, long-lasting perennial plants.

One of the best of these is the delightful Geranium maderense. This is a slightly frost tender perennial from Madeira. It has large pinnate leaves which have a tropical feel. Each plant forms a large dense clump up to metre in height and diameter. The flowers only appear after two or three years, but the floral effect is well worth the wait.

A huge stem appears in the middle of the clump, rapidly expanding until its many branches hold hundreds of bright magenta pink flowers, each with a contrasting deep maroon eye.

Unfortunately this wonderful perennial is a short lived one – it tends to be monocarpic and after its one and only flowering, it dies. Fortunately it is a prolific seeder, and a crop of seedlings will soon appear underneath the old plant. These can easily be transplanted.

As it is a touch tender, this plant will do best in a protected but cool area – under light shade suits it well. It flourishes among the Rhododendrons, bog primulas, hostas and maples of Taranaki, where it is almost a weed at times.

Not all the species are as tall as G. maderense, and among the smaller growing forms there are many that are ideally suited for the front of a mixed border, and as ground cover in sunny areas.

One variety we have grown for many years is Geranium clarkei ‘Kashmir White’. This
plant will grow in full sun or partial shade with stems can be as tall as 50 cm. The pale flowers, which are 4-6 cm across, appear pink rather than white, because of the pink veining in the petals. There is also a purple form of this species. You will not be surprised to read it is called ‘Kashmir Purple’.

When I first stared gardening the most common of the small true geraniums was probably the “Bloody Cranesbill”, G. sanguineum, its Latin name reflecting is common name, or vice versa. Its names, apparently, have nothing to do with the colour of its flowers, which in my experience are a lurid magenta pink, but rather the red colours the leaves take in the autumn.

It is an attractive plant all year round, in or out of bloom. The foliage is usually more distinctly cut than other geraniums, giving it a delicate appearance. The typically cup-shaped flowers can come in shades of pink, magenta and white, and give one of the best bloom displays of all the geraniums, the flowers can completely hiding the foliage.

If you are sick of the once fashionable white flowers and are looking for a garden to suit the more Goth-like members of your family, G. phaeum is just the thing for you. A medium sized plant with leafy foliage, this species comes complete with nodding flat flowers in a sombre purplish-red colour – almost black enough to satisfy the most angst-ridden teenager!

It prefers shade or semi-shade where it will make a good ground cover.

No comments: