Dendrobium is a diverse
genus of orchids with different cultural needs.
Many go through a growth phase and then a rest
phase during the course of one year, and must be
given water and temperature to match these
periods of growth and test. Flowers can last one
day to many weeks, depending on the type. Owing
to the extreme diversity of the genus, we have
categorized culture according to the following
Evergreen for several years, with thin, tall
pseudobulbs, terminal inflorescences, usually
appearing in the autumn or twice a year (see
Species such as Den. affine, Den. bigibbum
(phalaenopsis), Den. dicuphum and Den.
Culture Grow warm year round
(see below); 60 F nights; water and fertilize
heavily when roots appear from new growth; medium
light; reduce water and fertilizer after growth
finishes. If a short (three- to four-week),
cooler (55 F) dry rest is given, and then plants
are warmed again (60 F minimum), another growth
may mature during winter and flower in the
spring. Treat this growth as a summer growth
cycle. These grow well with phalaenopsis, except
for the rest period. Plants will go deciduous if
grown too cool and dry.
SPATULATA (Antelope Type)
Evergreen for several years. Most are large,
vigorous plants with long-lasting flowers in
summer to several times a year. Species such as Den.
antennaturn, Den. canaliculatum, Den. discolor,
Den. gouldii, Den. johannis, Den. lineale
(veratrifolium), Den. stratiotes, Den.
strebloceras and Den. taurinum.
Culture Warm all year (60 to
65 F nights, 75 to 90 F days); no rest period;
can be kept cooler in winter if dry; medium to
Most of the plants are pendulous, with leaves
all along the canes that most often drop with
onset of cooler, drier weather. One to five
flowers per node are borne from the nodes of the
leafless canes in midwinter through early spring.
Species such as Den. chrysanthum, Den.
friedricksianum, Den. nobile and Den.
Culture 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 or no water,
no fertilizer, cool nights (40 to 50 F). In other
words, forget about them.
Species such as Den. anosmum (superbum),
Den. crassinode, Den. falconeri, Den. fimbriatum,
Den. findlayanum, Den. heterocarpum (aureum),
Den. loddigesii, Den. moniliforme, Den. parishii,
Den. primulinus and Den. transparens.
Culture Same as Group 1, but
winter nights 55 F. Deciduous species need
virtually no water in winter.
Most are pseudobulbous plants with pendent
inflorescences. Species such as Den.
aggregatum (now properly lindleyi), Den.
chrysotoxum, Den. densiflorum, Den. farmeri and
Culture Summer give warmth
(60 to 90 F), medium light, medium quantities of
water and fertilizer. Winter keep cool (50 F
nights), medium light, just enough water to keep
pseudobulbs from shriveling, no fertilizer.
Leaves at top of pseudobulbs are large and
leathery, inflorescence erect, flowers commonly
Species such as Den. atroviolaceum, Den.
macrophyllum and Den. spectabile.
Culture Same as antelope
types, but cooler and drier when resting in
FORMOSAE (Nigrohirsutae Type) Canelike
pseudobulbs, with black hairs on leaf sheaths and
pseudobulbs often apparent, leading to the
popular name nigrohirsutae. Flowers usually
white, up to 4 inches across, two to three
together from near the end of the pseudobulb.
Long lasting. Species such as Den.
bellatulum, Den. dearii, Den. draconis, Den.
formosum, Den. infundibulum, Den. lowii, Den.
lyonii, Den. margaritaceum, Den. sanderae and
Culture Intermediate to cool
year round, 50 to 60 F nights, maximum 85 F days.
Water and fertilize when growing; give a slight
short rest (dry) when growth is completed. Keep
barely moist until growth starts again.
Among the popular types are Den.
linguiforme, Den. tetragonum, Den. gracillimum
and Den. cuthbertsonii (sophronitis).
Culture Depends on the
plant's native environment. It is generally safe
to grow them intermediate to warm (55 to 60 F at
night), drying them out in winter (or as growth
stops). Hybrids between sections vary in culture.
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