Referred to here as the Aussie dendrobes – dendrobiums

We are at the peak of orchid season in the garden. There can be few plants which carry the aura of luxury and exotica accorded to orchids. They belong to a huge and complex family, second only to the daisy family in number and go well beyond the common cymbidium. Yet they are not a plant that is common in New Zealand gardens.

Besotted by calanthes

The calanthe orchids are particularly rewarding as garden plants but you need to take the long view. We use them mainly as woodland plants. The blooms are a bit frost tender. Some we had on the margins were once hit by a memorable late frost but that was a one-off event. After about five decades of building them up, we have large swathes or drifts. In fact we have so many that a gardening ingénue who saw them recently drew the conclusion that they must be an unusual but easy bedding plant. Ah, no. But for those who have the time and inclination, they are a very rewarding branch of the family. Over time, they form a string of back bulbs below ground and can be increased from these.

For orchid enthusiasts who want the technical data, we understand that it is mostly forms of striata that are showiest for us. We have a pale lemon one which flowers in early spring and a much brighter yellow form that comes later. We used to have them under different species names but have come to the conclusion that they are more likely just different striata forms. Note: I have now been informed that the pale yellow calanthe shown is in fact Calanthe ‘Higo’ (C. sieboldii x C. aristulifera) which makes sense to us. We also use the white C. arisanensis but alas we failed with a lovely lilac species and appear to have lost it. All of these are evergreen varieties, though I understand there are deciduous species as well. The fresh spring leaves are large and could, at a pinch, be thought of as looking like pleated hosta leaves. A fair number of garden visitors over the years have asked us about the yellow flowered hostas. (Hint: hostas only flower in white or shades of lilac to purple.)

The Australian dendrobiums make compact, clumping plants with many smaller flowers and are pretty as a picture in the subtropical woodland areas. They combine very well with bromeliads and ferns and are an easy care garden plant. We have them in pinks, lilacs, white and yellow. We don’t know much about the hardiness of these. Ours are in positions where they never get frosted but they will get cold and they never turn a hair. They are probably similar to cymbidiums in hardiness.

Cymbidiums give long lived blooms, even outdoors

DIY bamboo stake

Cymbidiums are the usual florist’s choice and are surprisingly easy as garden plants, given the right conditions. All of ours are grown in the ground, not containers. We don’t get florist quality blooms but they last an amazingly long time in flower and put on a splendid show as long as I remember to stake the flower spikes at the right time. I see I started photographing the flower spikes a full two months ago and those same flowers are now a little weather beaten but still showy. These days I harvest stems of green bamboo which still have convenient leaf axils because I can gently engage the flower spikes in the leaf axils and don’t have to tie each one which makes staking much faster and more discreet. I admit this only works if you have a convenient stand of bamboo to harvest.

The jury is still out on whether we can get the disa orchids naturalised by the stream. They were fine for the first two seasons but the proof of the pudding is in the five to ten year cycle – whether they are still strong and flowering after that time. At this point it is not looking good. The native English field orchid, Dactylorhiza maculata, has gently ticked on here for decades but is romping away more enthusiastically now we are trying cooler, damper positions. We didn’t succeed with the masdevallias (though we probably didn’t try very hard) and the tropical orchids like phalaenopsis (moth orchids) won’t do as garden plants for us.

One of the easiest orchids to grow – pleiones

This week it is the pleiones which are the stars. Their flowering season is nowhere near as extended as some of the other orchids, but they form pretty carpets, are not at all tender and are dead easy to increase. Most bulbs will make one or two offsets a year. Along with the dactylorhiza, they are deciduous, becoming dormant in autumn. The yellow pleiones want more of a winter chill and have gradually died out for us but we have an abundance of purest white ones and an array of lilacs and purples.

These are not generally plants that you will find offered for sale at garden centres (which may be why they are not often seen in gardens). You probably need to find your nearest Orchid Society and enquire about sales tables. Orchid enthusiasts tend to be a different breed. At the risk of making sweeping generalisations, Orchid Society people are more often collectors than gardeners. More than any other horticultural group we have come across, orchid people have well above average technical knowledge and like to show off their treasures in bloom. They are also generous and encouraging to any novice who shows an interest. Much of our collection has come from Orchid Society people over the years. We cannot speak highly enough of them as a repository of knowledge about a very complex plant genus.

For details on how to multiply calanthe orchids, check out our earlier Outdoor Classroom on the topic.

First published by the Waikato Times and reprinted here with their permission.