This fantastic group offers a tremendous variety of flower forms
and colors to the orchid fancier. Native from Mexico to Peru in the American
tropics, the more than 100 species offer serious orchidists and taxonomists a
tremendous challenge in distinguishing one from another. Interestingly, male
flowers of species are equipped with an antenna-like trigger device which is
attached to the column. When irritated or bumped by a curious, unsuspecting
insect visitor, it fires the pollen-charged anther cap onto the insect's body,
where it adheres. This is one of the most unique developments among species of
this highly evolved family -- the orchids.
Catasetum flowers are usually either male or female; seldom are they perfect, i.e. hermaphroditic. Since flowers of the two sexes from the same species are significantly different, there has been considerable confusion regarding taxonomy in the genus. As interest increases in these exciting types, it is expected that even more effort will be devoted to clarifying these matters. The following cultural instructions are intended as a guide only; specific information can be obtained from the Recommended Reading list or from evidence obtained in the areas where the plants are native. This general cultural information may be applied to Catasetum, Coryanthes, Cycnoches, Gongora, Mormodes, Stanhopea, and their hybrids. Exceptions for Coryanthes and Stanhopea are outlined in the final paragraph.
GENERAL CONDITIONS
Catasetums produce fattened, fleshy pseudobulbs and are deciduous. These characteristics suggest that attention must be given to watering practices and a dormancy requirement. The plants grown here require year 'round warm house conditions with good air circulation.
TEMPERATURE
The plants can be grown at 75°-80°F. (25° Celsius) during the day, with temperatures falling to 60°-70°F. (18-21° Celsius) at night. Dormancy will occur in response to changes in day length, usually in the fall, and soon after flowering; temperatures need not be altered to induce or treat dormancy.
Catasetums can be grown with as much light as for Cattleyas or as little as for Phalaenopsis. However, growth is most vigorous under the brighter conditions and the heavier bulbs produced are capable of yielding more substantial inflorescences of better quality blooms. Generally, female flowers are produced in bright light; in some cases, near full sun conditions may be required to obtain this response. As the plants complete their flowering cycle, they will lose their foliage and require less light.
POTTING MEDIA, CONTAINERS, WATER and FERTILIZER
Plant Catasetum in a well-drained medium, e.g. New Zealand sphagnum moss,
tree fern, etc., and in a container which encourages good drainage; orchid pots
or wood slat baskets have proven effective. Repotting should ideally be done
just as the plants are making growth, usually spring. Watering may become more
regular and heavier as growth increases, producing more roots to satisfy the
plants' needs. These adjustments are made as days become longer, brighter and
warmer, resulting in heavy growth which will maximize potential for flower
production in the fall.
Of course, as the plant uses more water, it can also use more fertilizer,
preferably 20-20-20 at the rate of one teaspoon/gallon of water applied as
frequently as once each week. The fertilizer formula should match the potting
medium. Use 20-20-20 with tree fern, charcoal, or various inorganic aggregates,
but use 30-10-10 with fir bark. We recommend non-urea based fertilizers at half
strength. Non urea fertilizers provide 100% immediately available nitrogen,
which urea based fertilizers do not. We recommend Grow Mor fertilizers , which
also have micro nutrients. The micro nutrients provide strength for the new
growth and support for the flowers.
PEST AND DISEASE CONTROL
Catasetum foliage is susceptible to spider mite infestation. Watch the thin, soft leaves carefully for symptoms of their presence, being quick to eliminate problems as they occur; use a miticide, at the recommended dilution. If rot should develop in Catasetum bulbs, cut away the affected area or bulb, treating the cut surface with Captan, Dithane M45 or Banrot paste; do not water until the problem is arrested.
As Catasetum spikes become 4"-6" long, begin careful staking which may be helpful in encouraging good flower arrangement on the developing inflorescence. Be certain to leave the plant facing the same direction during inflorescence development. Do not probe the male flowers at any time, for these may be accidentally emasculated, causing them to fold prematurely.
|
NOTES FOR STANHOPEA, CORYANTHES, AND GONGORA While these three genera are from another tribe, their culture is nearly the same as that of Catasetum. These all produce basal inflorescences and therefore give best results when grown in wood slat or wire baskets, permitting the spike to emerge below. All will do well in intermediate conditions, although warmer conditions should cause no harm; light intensity may be best as for Phalaenopsis. Plants are evergreen to partly deciduous and may benefit from a brief period of dormancy, i.e. little water when growth is complete. |
The following information on Catasetum culture is from Bela Vista Orchids - a Brazilian orchid grower
The culture of Catasetums involves recognition of two distinct growth phases:
1. Active growth , which culminates with the onset of dormancy, i.e., the withering and loss of foliage;
2. Dormancy , which culminates with the onset of new growth.
At the beginning of active growth, watering is particularly critical because of susceptibility to fungal and bacterial disease, and attacks by insects. Some species begin to flower as soon as the new growth resumes; others flower upon maturation of the new pseudobulbs, occasionally as late as the onset of dormancy. When flowering, the principal danger to Catasetums is damage by insect pests.
Optimal control of water is achieved by maintaining the plants in covered area with enough light to support good growth and flowering. Glass panels or transparent plastic can provide suitable cover.
In order to avoid fungal disease, good ventilation is required, along with adequate air turnover.
Exposure of plants to insects is minimized by closing the sides of the area with a screen, e.g., 70% nylon shading, and maintaining access doors shut.
These precautions, taken together, can reduce disease by 70% and help insure successful cultivation.
REPOTTING
The best time to repot Catasetums is in the Spring, at the commencement of new growth with new roots showing. Different growers are successful with various types of pots and potting medium. We advise plastic pots for dry environments and porous clay pots for humid environments. The potting medium may be chosen from locally available materials and should be chosen to assure good aeration and accessibility to nutrition. Some of the suitable materials include Dicksonia sellowiana , fir bark and sphagnum moss. We use a mixture of fir bark, charcoal and perlite or sponge rock.
WATERING
With the advent of new growth at the end of dormancy, watering is resumed in the following manner:
At first, water only sparingly, taking care that water does not remain within the new growth longer than six hours. Do not water on days of high humidity but water the potting medium directly whenever it seems dry.
When new growth reaches 7-10 cm, increase and maintain heavy watering throughout active growth until the onset of dormancy. During active growth Catasetums require lots of water.
When dormancy starts to manifest by withering of the foliage, gradually reduce the quantity and frequency of watering; when leaf fall begins, stop watering completely and permit the medium to dry out.
FERTILIZING
Catasetums require heavy fertilization during active growth. We advise to begin fertilizing with the second watering after the end of dormancy, using a high nitrogen fertilizer such as 10-5-5 [30-10-10]; a balanced fertilizer such as 10-10-10 [20-20-20] is used for the remainder of the growing season. We use one third the recommended concentration [one tsp/gal] at EACH subsequent watering. A more convenient way of fertilizing continuously is to use a slow release fertilizer such as 14-14-14 OSMOCOTE at the rate of 1/2 tsp/pot.
There is a danger of losing the plant to rot if fertilization is started before the new growth appears.