Woodland orchids

At the south end of my garden is a roughly rectangular flowerbed, approximately 15 x 22 ft (4.5 x 6.7 m), shaded by a mature dogwood tree (Cornus florida). The dogwood bed catches rainwater running off the lawn, so unlike most of the shaded areas in the garden, the soil is fairly moist. It has also been enriched with organic material, the legacy my past attempts to grow vegetables there (hint: veggies don’t grow well in shade). About four years ago, I started turning the dogwood bed into a shade garden planted primarily with woodland perennials from North America and those regions of Asia that have a climate similar to the piedmont. Pride of place in my somewhat haphazard planting scheme goes to orchids, most of which bloom in spring.

Calanthe

Chinese, Korean, and Japanese members of the genus Calanthe are some of the best orchids for shady piedmont gardens. They have beautiful flowers, tolerate transplanting well, and although they prefer moist, well drained soil, they are remarkably drought resistant when necessary. Their new growth is somewhat tender, but they do not seem to be as badly damaged by late frost as some other Asian orchids such as Bletilla striata.

Hardy Calanthe species and hybrids are rarely offered by specialist orchid nurseries, but they are sometimes sold by nurseries specializing in woodland perennials. I have planted four species (C. striata, C. tricarinata, C. discolor, and C. reflexa) and two hybrids (C. Takane and C. ‘Kojima Red’). C. tricarinata is currently in bud, and C. reflexa blooms later in the summer. The other plants are all flowering now.

Calanthe discolor

Calanthe discolor is generally considered one of the hardiest Calanthe species. Its natural range includes Hokkaido, the northernmost Japanese prefecture, and it is often rated for growing in USDA zone 6. It’s not a particularly colorful orchid, but it has a neat and tidy appearance. My plant, purchased from Montrose Garden, has pale green sepals and petals, but dark brown clones perhaps offer better contrast with the white lip. When dumped out of its pot, the plant fell apart into several divisions. I planted them separately, and they are multiplying rapidly, with each division producing several new pseudobulbs.

I really like the Japanese name for C. discolor: ebine, “shrimp root.”

Calanthe striata

I previously featured C. striata under its synonym C. sieboldii. C. kawakamii is also considered a synonym for this species, although the Taiwanese plants with that label may prove to be less hardy than the Japanese plants labeled C. sieboldii.

C. striata is a significantly larger plant than C. discolor, with many-flowered inflorescences standing ~22 inches (56 cm) high. It has proven very vigorous in my garden; the plant had two inflorescences in spring 2017 and six this year.

Calanthe Bicolor

Calanthe Bicolor, the hybrid of C. discolor and C. striata occurs naturally in Japan and has also been produced in cultivation. It is intermediate in size between its two parents and variable in color. I really like this clone with its yellow lip from C. striata and its sepals and petals darkened to orange by the influence of C. discolor. C. Bicolor supposedly benefits from hybrid vigor, but my plant produces a single new growth each year and shows no inclination to multiply like its parent species.

Calanthe ‘Kojima Red’

‘Kojima Red’ seems to be an informal name, not a registered grex. Its parentage includes Calanthe discolor, C. striata, C. tricarinata, and C. aristulifera. Although richly colored, the flowers are barely the size of C. discolor.  I think I prefer the species and C. Takane.

Update, May 11, 2019:

Calanthe tricarinata

In flower and plant size, Calanthe tricarinata is roughly equivalent to C. discolor and ‘Kojima Red’.  The flowers nod, so a viewer mostly sees their backs.   I have to tilt them up to get a good look at the lip.  The flower supposedly resembles a monkey’s face.  I can’t see it..

Cypripedium

North Carolina is home to about 70 orchid species and natural hybrids, but most of the really attractive plants grow in sunny habitat in the mountains or coastal plain. The majority of orchids in the piedmont woods have little whitish or greenish flowers that would only appeal to a confirmed orchidoholic. The exceptions are our two native lady’s slipper orchids, Cypripedium acaule (pink lady’s slipper, moccasin flower) and Cypripedium parviflorum var. pubescens (large yellow lady’s slipper). I have previously discussed the wild populations of these species that grow nearby.

C. acaule is notoriously difficult to transplant and grow in the garden long-term, but C. parviflorum var. pubescens is generally considered to be one of the easiest lady’s slippers to cultivate. For years, I have itched to add one of the latter to my garden. Last autumn I splurged and bought a blooming-size plant.

Cypripedium parviflorum var. pubescens

I expected to get a single-growth division that might give me one flower this year. Instead, the plant has produced five flowers on four new growths. I’m not sure if I’ll be able keep it going long term–a potential complication is that although the species is native to the NC piedmont, most of the plants in cultivation probably originate from more northern populations–but the size and vigor of this particular plant surely gives me a head start.

Cypripedium parviflorum var. pubescens

This actually isn’t my first attempt to grow C. parviflorum. Long, long ago, when I lived in Michigan, I kept a seedling of Cypripedium parviflorum var. makasin in a pot on my windowsill. This northern variety did remarkably well in the relatively cool climate of Ann Arbor, steadily increasing in size and reliably producing small but highly fragrant flowers.  Unfortunately, it really did not appreciate the move from Michigan to North Carolina. One hot summer it went dormant early and never sprouted the next spring.

My late, lamented Cypripedium parviflorum var makasin in 2001.  I loved the dark, corkscrew petals, and it was ideal for growing in a small pot. The flower’s pouch was only about the size of my thumbnail.

About fifteen years later, I’m trying another Cypripedium species in a pot:  the Taiwanese Cypripedium formosanum.

Cypripedium formosanum

I originally planned to plant this C. formosanum in the dogwood bed, but several sources suggested that it has a tendency to start growing in late winter and is badly damaged by frost. I decided it would be safest to grow it in a pot, at least until it is large enough to divide, even though it may be tricky to keep the roots cool in mid-summer.