CALLISTAMost are bulbous plants with a pendent inflorescence.
Species: aggregatum, chrysotoxum, densiflorum, farmeri, thyrsiflorum, etc.
CULTURE: Summer--give warmth (60° to 90°), medium light, medium quantities of water & fertilizer. Winter--cool (50° nights), medium light, just enough water to keep bulbs from shriveling, no fertilizer.
SPATULATA("antelope" type) Evergreen for several years. Most are large, vigorous plants with long-lasting blooms in summer to several times a year.
Species: antennatum, canaliculatum, discolorgouldii, johannis, lineale (veratrifolium), stratiotes, strebloceras, taurinum.
CULTURE: Warm all year (55°-60° nights, 65°-90° days); no rest period; can be kept cooler in winter if dry; medium to high light.
DENDROBIUMMost plants pendulous, leaves all along canes. Flowers 2-5 per inflorescence, from upper nodes of leafless canes.
Species: GROUP 1 -chrysanthum, friedricksianum, nobile, wardianum. GROUP 2-anosmum, crassinode, falconeri, fimbriatum, findlayanum, heterocarpum (aureum), loddigesii, moniliforme, parishii, primulinum, transparens.
CULTURE: GROUP 1-Growth period in summer-give warmth, water, and fertilize heavily from when roots appear until top leaf appears on canes. Then give high light, little to no water, no fertilizer, cool nights (40°-50°). In other words, forget about them! GROUP 2-Same as Group 1, but winter nights 55°. Deciduous species need virtually no water in winter.
LATOUREALeaves at top of pseudobulbs are large and leathery, inflorescence erect, flowers commonly yellow-green.
Species: atroviolaceum, macrophyllum, spectabile, etc.
CULTURE: Same as antelope-types, but cooler and drier when resting in winter.
FORMOSAECane-like pseudobulbs, with black hairs on leaf sheaths and pseudobulbs often apparent. Flowers usually white, up to 4" across, 2 to 3 together from near the end of the pseudobulb.
Species: bellatulum, dearii, draconis, formosum, infundibulum, lowii, lyonii, margaritaceum, sanderae, schuetzii.
CULTURE: Intermediate to cool year 'round, 50°-60° nights, max. 85° days. Water and fertilize when growing; give a slight short rest (dry) when growth is completed. Keep barely moist until growth starts again.
PHALAENANTHEEvergreen for several years, with thin, tall pseudobulbs, terminal inflorescences, usually appearing in fall or twice a year (see culture).
Species: affine, bigibbum, dicuphum, phalaenopsis, williamsianum.
CULTURE: Grow warm year 'round (see below); 60° nights; water and fertilize heavily when roots appear from new growth; low to medium light; reduce water and fertilizer after growth finishes. If a short (3-4 week), cooler (55°), dry rest is given, and then plants are warmed again (60° min.), another growth may mature during winter and bloom in spring. Treat this growth as a summer growth cycle. These grow well with Phalaenopsis, except for the rest period.) If you must keep plants cool in winter, keep them bone dry until weather warms, then water as growth appears. Plants will go deciduous with this cool/dry treatment.
OTHER SPECIESlinguiforme, tetragonum, gracillimum, cuthbertsonii (sophronites).
CULTURE: Depends on the plant's native environment--try to find out. It is generally safe to grow them intermediate to warm (55°-60° night), drying them out in winter (or as growth stops). Hybrids between sections vary in culture.
Prepared by: Education Committee, American Orchid Society