COLLECTOR’S NOTEBOOK

Orchids for Everyone Richard E. Weaver, jr.

Orchids hold a fascination for plant growers that few other plant groups can match. For the gardener their beauty and rarity, and the challenge of cultivating many species, make orchids par- ticularly desirable subjects. Growing hardy native orchids has become a somewhat controver- sial subject, however, because most of those offered commer- cially have been collected in the wild, and wild populations of many species are becoming seri- ously depleted. Native orchids are also difficult to propagate. Only a few species, notably the large yellow lady’s-slipper (Cyp- ripedium calceolus var. pubes- cens), increase reliably in cultiva- tion. In addition, most native or- chids are to nearly impossible Bletilla stnata grow from seed with techniques presently available, and they have not yet responded to propa- them without having to worry several of the Japanese species of gation by tissue culture, like about endangering the species in Calanthe: C. nipponica, C. many of the tropical epiphytic the wild. In addition, these tricarinata, and C. discolor and orchids. species are more attractive than its-varieties. But those of us who want to many of our native orchids; they Because the propagation of grow orchids in our gardens now are easy to cultivate; and they are many hardy orchid species is have an alternative. Several Asi- hardy in most parts of the Umted difficult, gardeners are often re- atic species can easily be propa- States. I am referring particularly luctant to attempt it. But I urge gated both vegetatively and from to Bletilla striata, often sold as them to try. Bletilla and seed, so we can obtain and grow the "hardy Chinese orchid," and Calanthe are good choices with which to start, because success is backbulbs, but these have prefer to separate them by gently virtually assured. evolved as a safeguard, so that if twisting them apart. If a knife is Before attempting to propagate the leading tip of the rhizome is used, it is important to inspect these plants, it is important to damaged, or if the season’s aerial the backbulbs carefully for any understand some basic facts of shoot is destroyed (perhaps by a latent buds in order to avoid orchid growth. Most orchids late frost), one of these latent damaging them. Again, the lead- grow sympodially, that is, each buds will break dormancy and de- ing pseudobulb can be replanted shoot grows to maturity and then velop into a shoot. Thus the in the garden. The backbulbs can stops growing, whether it flowers damaged plant will still be able to be planted in a propagation or not. That shoot is then suc- grow. frame, but because the shoots ceeded by a similar one, which These latent buds also enable they produce are delicate and develops from an axillary bud us to propagate Bletilla and slow-growing I prefer to start borne on the rhizome. Old shoots Calanthe, as well as other or- them in a seed pan. I use a me- often live for several years, still chids, by vegetative means. If we dium consisting of 2 parts peat capable of food production and separate them, and the backbulb moss, 1 part vermiculite, and I storage but incapable of growth to which they are attached, from part perlite. The backbulbs or flower production. In terres- the leading shoot, each will de- should be situated so that their trial orchids the rhizome is usu- velop into a separate plant. The tops are just below the surface of ally underground. In many genera procedure is simple. For B. the medium. Place the pans m a the shoots themselves consist of striata dig up the plant in the shaded spot in a greenhouse or two distinct parts: an above- spring before the new shoots have outdoors, and keep the medium ground part, which includes the emerged, and carefully clean the moist. The tender shoots are very foliage and produces the flowers pseudobulbs so that each one is attractive to slugs, so it is best to and in temperate regions usually clearly distinguishable. Be extra apply a commercial slug bait as . dies back at the end of each sea- careful to avoid damaging the soon as the shoots appear. Leave . son ; and an enlarged underground leading buds in the process. Sever the plants in the pans under part, attached to the rhizome, the rhizome between each fluorescent lights or m filtered which serves as a food-storage or- pseudobulb with a sharp knife or sunlight until the following gan. The underground part varies pruning shears. The pseudobulb spring and then plant them m in structure and appearance from with well-developed buds may be their permanent place in the gar- genus to genus, but in Bletilla replanted in the garden, and the den. and Calanthe it is a pseudobulb shoots should develop and flower Other orchids with corms or similar to the aerial ones of normally. The backbulbs should underground pseudobulbs should epiphytic orchids (in Bletilla the be planted in a propagating frame, respond similarly to Bletilla and structure is often referred to as a covered with about 5 cm of soil Calanthe. Experimentation corm).( . and mulched lightly. They must should produce some interesting The pseudobulbs of Bletilla never be let dry out. The and valuable results. I hope that and Calanthe live for several backbulbs should produce small success with these will lead to years, and if an established plant shoots the first season, and the experimentation with other of either genus is dug up the resulting plants should flower the species and that eventually structures appear as a string of second season. My expenence methods will be found for prop- beads, attached by the rhizome. has been that backbulbs up to agating more of these wonderful The old pseudobulbs, referred to five years old should produce plants. as backbulbs, function primarily shoots if treated in the manner to store but associated with descnbed above. food, Richard E. Weaver, Jr, the former each are latent buds often not The procedure for Calanthe horticultural taxonomist at theAr- visible to the unaided eye. species is similar. The backbulbs nold Arboretum, now operates Normally such latent buds would of this genus are bome very WE-DUNursenes in Marion, North eventually decay along with the closely together, however, and I Carolina.