V OLUME 17, ISSUE 1 J ANUARY— FEBRUARY The Trillium 2007 Piedmont Chapter North American Rock Garden Society Chapel Hill, Durham, Raleigh, NC Orchids in the Garden Orchids are among the most universally admired of all plants. Once their cultivation requirements became generally known, the epiphytic species exploded in popularity, and are now among the most popular of houseplants. The terrestrial spe- cies lagged on behind, and except for the slipper orchids, are still less commonly cul- tivated, at least in temperate climates. Plants of some of the tropical terrestrial gen- era, such as Sobralia and Arundina, are too large for the hobbyist grower to handle. Until recently many of the temperate orchids were considered difficult to grow, and most were available only as collected specimens. A few species, such as Bletilla striata, have long been popular garden plants. Within the last 20 years great strides have been made in the seed propagation of other terrestrial genera, and many wonderful plants, notably Cypripedium spp. and Calanthe spp., are now readily available to garden- ers. This talk will give an overview of some of the orchids I have grown in my gar- dens, with tips on cultivation and propagation. Obviously we will be concentrating on terrestrial orchids here. However a single epiphytic species is native to North Carolina and may possibly grow in a shel- tered spot, such as a courtyard or a screened porch, in the Raleigh area. Extremely Bletilla striata rare but apparently still extant, Epidendrum conopseum (E. magnoliae) has been collected only at Lake Waccamaw in Columbus County. It is an attractive plant with cane-like stems 5-10 inches tall, and terminal clusters of greenish (Continued on page 2) Seneca Hill Nursery I started Seneca Hill Perennials, in a casual sort of way, roughly 15 years ago, when I was still a tenured professor of economics at SUNY-Oswego. As I recall, my very first venture involved potting up some Miscanthus sinensis ‘Zebrinus’ , sticking it in a yard sale, and mar- veling at how fast it went. My first serious venture came when Mojmir Pavelka, of Euroseeds, offered me tubers of Arisaema candidissimum, Epidendrum conopseum (E. magnoliae) and I imported a boxful (sweating mightily over the risk I was taking; that check for a few hundred dollars looked big to me in those days, when we still had four children at home). I had no trouble peddling the arisaemas at an obscenely low price, and soon people were writing to ask what other “choice” plants I had to sell. I had none, but I was determined to do better. Between various friends who were much more sophisticated gardeners than I, the Internet, and a growing ref- erence library, I gradually wet my toes in the wonderful world of horticulture. Roy Herold and Nina Lambert deserve particular mention for getting me started growing cyclamen, and Steve Marak for piquing my interest in aroids, but I (Continued on page 8) (Continued from page 1) with a green to purplish-brown perianth and a white or pink or bronze-colored flowers. This species may perhaps be lip, and scapes to 18 inches tall. This species is long-lived in worth a try permanently mounted on the bark of an ever- the garden, and spontaneous seedlings were common at WE- green tree, but it would probably best be grown on a slab DU Nurseries. of bark or tree fern so it could be taken indoors during Closely related but extremely cold weather. much showier, C. sieboldii has beautiful, Plants of the genus Bletilla are the most readily available large, concolor bright and commonly grown hardy orchids in the U.S. Native to yellow flowers. The both China and Japan, B. striata is the most familiar and Takane hybrids, with easily grown species; with its bold plicate foliage and pur- these two species as ple and lavender, cattleya-like flowers, it is a handsome the parents, have and very satisfactory plant. It is remarkably adaptable, flowers in a wide growing well in gardens from southern Ontario to the color range, includ- tropics. A variety of selections are available, with white or ing many oranges pink flowers and and bronzes. Among variously varie- my favorite species, gated foliage. The C. tricarinata also oc- remaining species, curs in the Himala- all Chinese, are yas, and the Japanese smaller and less plants have been seg- showy, but perhaps regated as C. torifera. more charming; It ranges to Hok- they are also less kaido, the northern- cold-hardy. The most Japanese island, low-growing B. and is among the formosana has pink hardiest of all the Calanthe discolor and white flowers Calanthes. The ex- on a branched in- quisite flowers, with a chartreuse perianth and a maroon lip, Bletilla formosana florescence, and are quite large, but are not as many per spike as in the previ- the variable B. Yokohama is its hybrid with B. striata. The ous species. Probably the hardiest of all, C. nipponica is sel- beautiful yellow-flowered B. ochracea is slender and later- dom cultivated. It blooming. We have a large and vigorous, un-named spe- is a small slender cies with either pink or yellow flowers that blooms into species with yellow early summer here in Florida. Dr. Warren Stoutamire, of to yellow-green the University flowers, and though of Akron, has very charming, is crossed many not particularly of these spe- showy. A desire- cies, producing able but less hardy a variety of species, and one beautiful and that struggled at garden-worthy WE-DU Nurseries, plants. All C. aristulifera closely these species resembles C. sieboldii and hybrids are and C. discolor, but best grown in with concolor white moist to dry or pinkish flowers. Bletilla ochracea soil in good Calanthe species are light, but shaded from the afternoon sun. best grown in a soil that does not dry The Japanese species of Calanthe are certainly among the out severely, and Calanthe sieboldii showiest of hardy orchids. The easiest species is C. discolor (Continued on page 3) Page 2 Volume 17 Issue 1 January — February 2007 (Continued from page 2) moist but well-drained soil. The relatively recently de- under high deciduous shade; at least C. sieboldii and C. dis- scribed C. kentuckiense is found in scattered localities color can take morning sun as well. throughout the Southeast. It differs from the preceding in its longer peduncle, and its larger, pale yellow or ivory lip The genus Cypripedium is with a distinctively shaped orifice. This is among the most made up of 48 species vigorous of all lady’s-slipper species, and is a very fine gar- distributed throughout den subject. the North Temperate Zone, with the majority The showy lady’s-slipper, Cypripedium reginae, is native to being native to eastern fens and meadows from Newfoundland and Saskatchewan Asia; a few extend into south to Arkansas and North Carolina. It is distinctive in the subarctic and fewer its white perianth with flat petals and large, subglobose still are tropical. These rose-colored lip. It regularly produces two flowers per are among the most de- stem and forms impressive clumps in the wild. It is best sirable of all orchids for grown in full sun or light shade in moist, slightly basic to the garden. Many of the neutral soils. I used a layer of mortar pieces in the bottom spectacular Chinese spe- of the planting hole with good effect. All of the species cies are now becoming discussed so far are clump-formers, but a few Asiatic spe- Calanthe tricarnita available, as are an in- cies are rhizomatous and colonial. The best-known, Cypri- creasing number of interspecific hybrids. Here I will con- pedium japonicum, is native to Japan and China, where it of- centrate on some of the easier species that I have grown ten grows in bamboo thickets. It is a distinctive and strik- over the years. The American yellow-flowered lady’s- ing plant with its two, large, fan-shaped leaves borne on a slippers are among the most reliable orchids for general stem above the ground. The flower is equally distinctive garden cultivation, and seed-grown plants are now avail- with its able from a number of sources, as are nursery-grown divi- green peri- sions. The commonest and most widespread species in- anth and cludes several quite distinct varieties, which are somewhat large, confused nomenclaturally. The large-flowered variety with drooping, a generally greenish perianth and a mild, rose-like fra- cleft lip grance is now known as C. parviflorum var. pubescens. It oc- which is curs in rich, mesic woods from Newfoundland to Alaska, pale pink south to Arizona and Georgia. The small-flowered variety with red with a generally markings. maroon peri- This was anth and a vigorous in strong, sweet my Boston fragrance is garden, in presently dense Cypripedium reginae known as C. shade on a parviflorum var. pronounced slope. A close relative, C. formosanum is native makasin. Its to Taiwan. It is more refined than the preceding in all range largely respects, with a fuller flower that is all white except for the overlaps that of red markings on the lip and the perianth. It is also less the preceding, cold-hardy and considerably easier to grow. It is consid- but it is absent ered by some to be the easiest of the genus. In my Boston from the South- garden I dug it each fall, overwintered it in the soil at the east. Both spe- bottom of a cold frame, and replanted it in the garden cies make beau- each spring; it bloomed reliably.