CATTLEYA dowiana is often considered difficult to grow in cultivation when, in fact, it is a vigorous, free-flowering, easy-to-grow plant if a few basic rules are followed.
The most important rule is to grow C. dowiana so its roots dry quickly and are never subjected to a wet, soggy medium. For this reason, C. dowiana is either grown in clay pots that barely accommodate the plant and one new growth, or it is planted in hanging baskets.
Cattleya dowiana also likes to be kept dry when it is not actively growing and the easiest way to retard its growth or kill it is to overwater it during the cool winter months when it is dormant. In its native habitat, C. dowiana grows at the tops of tall trees in the jungle where its roots dry out rapidly after a rain. It also has a dry resting period in the jungle in December and January.
Ignoring C. dowiana’s need to dry out will cause the roots to rot and eventually the pseudobulbs will decay. Unlike black rot of cattleyas, which begins on the youngest, softest growths, C. dowiana pseudobulb rot begins at the base of the oldest pseudobulb and progresses through the rhizome and kills the youngest pseudobulb last. Pseudobulb rot is always fatal, and it is the main reason virtually all of the fine old clones of C. dowiana from the turn of the century are no longer in existence.
Cattleya dowiana requires lots of sun and, if you want to enjoy its spectacular four-to five-flowered spikes, you must provide this. Plenty of moving air from fans is beneficial, too. This helps keep its leaves cool and aids in drying its roots.
In the Northern Hemisphere, C. dowiana begins growing in early spring, flowers in mid to late summer and, after flowering, goes dormant until the following spring. It requires frequent watering when it is actively growing, but little water after flowering until it begins growing in the spring.
Fertilizer is not an essential ingredient to growing C. dowiana well. If you grow in bark mixtures, a light fertilizing during the active growing season is needed. Apply 1/4 teaspoonful of a soluble 20-20-20 per gallon of water every two weeks until buds appear in the sheath. After that, do not apply any fertilizer until the plant begins growing again in the spring. Never use a slow-release fertilizer because this may continue to feed during dormancy, which can contribute to pseudobulb rot.
Several orchid companies have been selling C. dowiana in recent years, so plants should be available for anyone who wants to grow this delightful species. In addition to its beautiful color, C. dowiana has a hauntingly lovely fragrance that can fill your whole house and greenhouse, and will certainly fill your soul. — A. A. Chadwick.