Orchid season

There are some immutable constants in this universe; the speed of light never changes, pi is always the same, and each glasshouse, no matter how big it is, is always about 20% too small.
I thought I had addressed the smallness of my glasshouse (or polycarbonate house to be more exact) a summer or two ago, by expanding it by one fifth, but now I find, miraculously, it is still 20% too small.
Last weekend I pricked out this year’s crop of Pacific Coast Native Irises, and got the potted tuberous begonias out from under the glasshouse benches. They had spent the winter there, having a dry rest on their sides but it is now time for them to be kicked back into life by being watered.
I was scrambling for space. I had to shuffle around the various potted special plants, and even then could hardly fit everything in. I was especially keen to make some room because a friend had offered me some pots of one of my favourite plants, the little Australian Dendrobium orchids. As much as I tried, I just could not find any space at all.
That is a pity because this is the time of year for orchid societies to mount their spring shows. The Masterton show will be held on October 3 and 4, while the Hawkes Bay society will be holding their Sarcochilus show on November 7 in the Taradale Town Hall. The Masterton show will feature a large sale of very affordable orchid plants, and I was thinking I could expand my collection
I have a particular fascination with the Australian Dendorobiums – ‘dendrobes’ as orchid lovers call them.
They are derived from a number of epiphytic (growing on the bark of trees) and lithophytic (growing on rock faces or boulders) species, and they are smaller growing species (usually less than 30 cm) with reliable spring flushes of many flower spikes.
Again, they will do well in a special growing house with shade cloth walls and a solid roof to keep out the worst of the winter rains. Failing that, a nice north facing verandah will do fine. They enjoy the winter sun but need to be kept shaded over the hottest months.
I find they respond well to a small application of a long-term fertiliser. I know specialist growers go to all sorts of trouble, making up special feeding mixes for different times of the year, but for the average home gardener it is probably not that necessary – you will get perfectly fine results from the standard formulae.
Plants should be kept moist year round, although they can be allowed to dry oput a little in the middle of winter. Do not let them sit in water though, and make sure the pots are kept off the ground, as earthworms will enter through the drainage holes and make a mess of the bark mix.
The best-known species is he Australian King Orchid, Dendrobium kingianum, now officially Thelychiton kingianus. It is arguably the easiest Dendrobium to grow. It is the fastest growing and the most forgiving of all the Australian orchids, which makes it ideal for the novice grower. It ranges in colour from true albino white to a rich cherry purple, with bicolour shades of white with a rich violet eye. Breeders are currently working on lemon shades, true salmons and unusual sunset colours as well.
Take advantage of the opportunity to get along and see what specialist orchid growers are up to in their shows. Be warned though – you might find your glasshouse (or verandah) is about 20% too small.