Catasetums - The winter rest of the species and hybrids

The subtribe Catasetinae includes species of the genera Catasetum, Cycnoches, Clowesia, Mormodes and their intergeneric hybrids, being perhaps the most famous examples of winter dormancy in the orchid growing world. The changes the plants undergo during the dormancy period are so visibly dramatic that untrained individuals might mistake the onset of this phase for the appearance of a fungal or bacterial disease. Leaf loss in Catasetinae is strictly correlated with the flowering time, as some species bloom from summer until late autumn, before the dormancy period begins, while the rest flower after losing their leaves, on the bare bulbs.

Starting from the moment the leaves yellow and dry, followed by their fall, growers will stop fertilizing and reduce watering frequency, approximately in the second half of autumn, when temperatures and photoperiod also decrease. Watering, although less frequent, will continue until mid-winter, as long as leaves are still attached to the pseudobulbs. Dormancy can be induced, if needed, by completely stopping watering if the plants have not naturally entered dormancy at the beginning of winter, resorting to occasional watering, ideally by misting, only if excessive shriveling of the pseudobulbs is noticed, which normally have sufficient reserves of water and nutrients to survive the winter and equally to provide energy for new growth development. Also during this dormancy period, transplanting and division will be done, avoiding these operations once new roots have penetrated the growing medium. New growths will not be watered until they exceed 8–15 cm in height, when leaf unfolding will also be noticeable. As long as the leaves are tight and grouped, there is a risk that administered water will penetrate between them and cause fungal and bacterial diseases.

Once the dormancy period is over, the amount of water administered will be gradually increased, adding fertilizers every second watering, to meet the accelerated growth rate these plants are known for.

Note:

During the dormancy period, plants can still remain in areas with good natural or artificial light - in nature, this factor does not change.
If significant dehydration of the bulb is noticed, hydration by fine misting is recommended - both the bulb can be misted, provided it is well cleaned of debris left after leaf drop, as well as the substrate.