Tropical Punch

Whenever the topic of orchids comes up in conversation, it triggers thoughts of tropical jungles with orchids dripping from the branches of trees. Or one might think of large display greenhouses, such as those at the Montreal Botanic Garden, Kew or, of course, our own Bloedel Conservatory, which has an ever-changing display of these exotic blooms year round.

Credit: John Glover

Whenever the topic of orchids comes up in conversation, it triggers thoughts of tropical jungles with orchids dripping from the branches of trees. Or one might think of large display greenhouses, such as those at the Montreal Botanic Garden, Kew or, of course, our own Bloedel Conservatory, which has an ever-changing display of these exotic blooms year round.

But Orchidaceae, the orchid family, has 796 genera and 17,500 species – and not all of them are tropical. In fact there are orchids on every continent of the globe and we have some rather special ones native to Canada – but more on that later. As most of you know, I grew up in England, where in springtime several rather lovely ground, or terrestrial, orchids bloom profusely. They are mostly members of the Orchis or Dactylorhiza genera. When I was first told they were orchids I didn’t really believe it, but a close inspection of the individual flowers soon verified that they were indeed. So imagine my great delight when a gentleman who had moved to B.C. from Europe and had collected hardy orchids all his life donated his entire collection to UBC Botanical Garden in the early 80s. I don’t quite remember how many different species were planted in the European section of the Alpine Garden, but over the years only two of the hardiest species adapted to our soil conditions and survived. Both belonged to the genus Dactylorhiza. Over the years they cross-pollinated freely and seeded themselves in other continental areas of the Alpine Garden, and because they were deemed rather exotic they didn’t get weeded out. Consequently, plopped in the middle of the South African section or the North American section, there were pretty clumps of European orchids! To this day there are several Dactylorhiza foliosa that bloom happily in the Australian section.

These hardy European orchids are not easy to find in general nursery stock. One has to seek out specialty growers, or attend plant sales given by organizations such as the Alpine Garden Club of B.C. For those of you who like to grow plants from seed, there is a limited supply of seed available each spring at The Shop in The Garden at UBC. Dactylorhiza foliosa is robust, with 4 to 6 lance-shaped basal leaves that are often brown or purple spotted. Each flowering stem is up to 60 cm (2 ft.) in height and the dense terminal raceme of flowers takes up the top 13 cm (5 in.) or so. The flowers are bright purple. The other species, D. maculata, has many of the same characteristics. It produces spotted leaves and usually bears white to rose-pink flowers. D. elata boasts a rather more robust growth habit. The linear leaves are again brown or purple spotted and the deep-purple flowers are interspersed with long protruding bracts. Dactylorhiza fuchsii is very similar to D. maculata and is thought by some to actually be a subspecies of it.

The flowers can be pale pink to white or mauve-spotted deep red or purple. Orchids prefer full sun to the semi-shade of deciduous shrubs. Vigorous clumps may be carefully divided in early spring just as the new shoots pop out of the ground. The amazing thing about the orchids at UBC is that they seem to proliferate in open, well-drained soil. However, where I grew up they loved marshy areas that were moist in spring but drier during summer months. But there is no doubt they do like rich, but well-drained soil with plenty of leaf mould worked in.

I have always encouraged gardeners to rake up and collect dry fallen leaves in the fall. Fill a plastic garbage bin about two thirds full, then whisk them round with a line trimmer until they are all cut into tiny pieces. There you have it: instant leaf mould, which can either be dug in right away or bagged and kept in the potting shed for later use – such as when you plant out your hardy orchids. While the European orchids are mostly suited to warmer zones, those of you in northern areas should not be discouraged, as there are some really amazing native orchids that, believe it or not, occur clear across our country from the interior of B.C. right through to Newfoundland. They are most commonly called lady’s slippers and belong to the genus Cypripedium. The yellow lady’s slipper, Cypripedium calceolus, has light-green, ovate to elliptic foliage 10 to 13 cm (4 to 5 in.) in length. In summer it bears purple-brown (though sometimes pure-yellow) flowers 9 cm (3 1⁄2 in.) in length with twisted petals and a large, deep-yellow lip. The flowers are borne singly or in pairs. This orchid also likes to grow in rich, leafy, well-drained soil, but it prefers dappled shade. This particular species, and only this one, prefers a slightly alkaline soil. So top-dress it annually with a sprinkling of dolomite lime, or bury a small piece or two of broken-up concrete nearby at planting time. I have happy memories of seeing drifts of this plant when leading a tour of the Friends of the Garden to Alberta. We were tipped off about a boggy area near Hinton, just out of the Rockies, and it truly was a memorable sight. Much more recently, when taping Spring, we did a show from Newfoundland and again saw drifts of these wonderful yellow flowers in Gros Morne National Park. And to underline the hardiness of these orchids, a friend, the late Ken Girrard, used to rescue yellow lady’s slippers from building sites, and big clumps of them flourished in his zone-3 Calgary garden. While Cypripedium acaule is not as showy, it does have a spectacular flower on a single stem coming up from a pair of elliptic leaves 10 to 23 cm (4 to 9 in.) in length. The slender flower stalk is 23 cm (9 in.) tall and the solitary, pale greenish-brown flower has a large, dusty-pink lip. C. acaule requires a semi-shaded woodland location with a rich, leafy, well-drained soil. But perhaps the showiest of the three is Cypripedium reginae. It has 3 to 7 lance-shaped leaves that are 10 to 23 cm (4 to 9 in.) long and the flower stems can reach 75 cm (2 1⁄2 ft.) in perfect conditions. The absolutely gorgeous flowers, borne singly or in pairs, are 10 cm (4 in.) long and have pure-white petals and rose-pink lips. They are like Georgia O’ Keefe paintings! Again, we saw magnificent specimens in Newfoundland. Particularly stunning, Cypripedium spectabile appears to be a selected form of C. reginae with a striking darker-pink lip. There are some important points to mention about all these Canadian native orchids. None of these plants should be lifted from the wild; they are on the endangered list. Grow only from seed or buy plants from reputable native-plant nurseries. Successfully growing plants may be divided very gently and carefully in early to mid spring. Replant immediately, and place some soil from the original area in the planting hole, as it contains beneficial fungal mycorrhiza. And remember, all the Cypripedium orchids prefer shade. There are, of course, hardy orchids from other continents and Bletilla striata, on display at the UBC Botanical Garden, is one of my favourites.

It comes to us from cooler temperate areas of China, Taiwan and Japan and is hardy to zone 5. This is another terrestrial orchid that’s ideal for woodland areas of the garden or tucked under deciduous shrubs. Lovely, oblong, lance-shaped, rich-green leaves grow to 30 to 45 cm (12 to 18 in.) in length. The magenta flowers are borne in loose terminal racemes, each flower 2.5 cm (1 in.) across and very tropical looking. The key to success with this one is providing humus-rich, well-drained soil in partial shade, with an annual fall mulch of leaf mould. It can be divided in early spring and, most happily, it does seed quite freely.

The following plants are hardy to the zones number indicated (turn to page 6 for our zone chart): Bletilla striata – zone 5 • Cypripedium acaule – zone 3 • C. calceolus (yellow lady’s slipper) – zone 3 • C. reginae (showy lady’s slipper) – zone 2 • C. spectabile (showy lady’s slipper) – zone 3 • Dactylorhiza elata – zone 6 • D. foliosa – zone 7 • D. fuchsii – zone 5 • D. maculata – zone 5 David Tarrant is a well-known gardening expert, author, and host of Spring, on HGTV.