Cool Growing Epiphytes

Cattleya
Renowned for their flamboyant, often fragrant blooms, orchids in this genus
are found in Central and South America (65 spp.)  - not to mention all the artificial
hybrids. they are sympodial epiphytes with elongated pseudobulbs each with one
leaf (unifoliate) or two leaves (bifoliate). Flowers are produced from the new growth.

Cultivation

Grow in pot or basket of coarse mix. (bark, fern fibre, coconut husk chips, charcoal) or on a slab.  Provide bright light, high humidity and continual air movement. Repot every 2 years allowing just sufficient room for the new groth. Water frequently over summer, allow to dry out between watering, and keep plant drier over winter.

Cymbidium
Sypodial epiphytes and terrestrials, distributed fron Northern India and China to Australia.
Growing from humid lowland forest to mountainous areas. Many have prominent thick
pseudobulbs with long slender-like leaves, others have slender leafy stems. The flowers
are either borne singly or on long arching racemes. Cymbidium has been intensively
hybridised resulting in thousands of hybrids.

Cultivation

Pot into a freely draining but moisture-retentive mix. Commercial mixes are generally available.
Terrestrial spp. need a smaller particle mix than the epiphytes. Repot every two to three years.
Provide gright light and good aeration. Expose the plant to winter cold  to intiate flowering and mist  the maturing growth  of the winter-spring-flowers frequently during summer evenings.

Oncidium
Included are many wonderful orchids that are popular with growers. They are sympodial epiphytes from Florida, West India, central America and South America, with thin roots and distinct pseudobulbs, each with one to four leaves.

Cultivation

Spp. from high altitude are cool growers, whereas those from the lowlands need heat
grow in a pot of coarse mix (underpot rather than use too large a pot)  or on slab, in
shade to bright light and with buoyant air movement. Some spp. need to dry out between
watering, others resent dryness.

Stanhopea
Astonishing Orchids (70 spp.) from Mexico, Central toSouth America, always attract attention.
Sympodial epiphytes with crowded pseudobulbs that each have a single large pleated leaf.
The flowers are carried on stiffly decurved racemens and the buds develop with incredible
speed and open with a distinct popping sound. The large waxy , often colourfully marked flowers, which only last three to four days, have a strong almost overpowering fragrance.
Also known as the 'upside-down ' Orchids.

Cultivation

These orchids are generally very easy to grow and many spp. succeed in shadehouses.
Because of their pendent racemes, the plant must be grown in baskets. Use a medium to
coarse epiphytic mix and provide moderate light, high humidity and buoyant air movement.
Water frequently when in growth, keep drier after new pseudobulbs have filled out, but don't
allow the plant to dry out comletely. Occasional dressing of dolomite can improve flowering.

Zygopetalum
This genus of 16  spp. occur in Brazil. They are clumping sympodial epiphytes or terrestrials with prominent leafy pseudobulbs. The thick-textured flowers have interesting colour patterns on the segments, especially the broad labellum. Many artificial hybrids are also available.  Name derived from Greek word "zygon" meaning "yoked petal"

Cultivation

Strong growers with thick roots. Pot in large containers of coarse bark-based mix or coconut husk chips. Water  and fertilise regularly when in active growth. Provide high humidity and buoyant air movement, with shade in summer and bright light in winter. Keep leaves dry in winter to avoid leaf spots.

Information from "Starting out with Orchids by David L. Jones"