Checklist for November and December

Cattleya

Growers of just about all levels of expertise will have begun to notice autumn conditions by now. Days are becoming shorter, so cooler; the sunlight has less intensity because of the sun’s lowering angle, nights are longer and usually cooler. Plants are responding by slowing and becoming ripe their growth in preparation for winter.

The first cultural change get noticed should be a cut frequency of watering, when the plants dry out more slowly. This is a function of both the cut day length and lower temperatures, as well as the plants’ slowing growth rate. Decreased water needs indicate a decreased need for fertilization. Note that the key word is decreased, not eliminated. Feed less frequently and at lower dosage, but feed. Growths, made during summer’s heat, and relatively soft and green, will be ripening — hardening — in preparation for a brief period of the rest (in many cases).

Many of these making growths ripe will have a sheath, being a sign that the coming winter or spring flowering season is going to happen. In some cases, these protective coverings will have been evident since as early as July. (Early sheath development does not mean early flowering on plants with winter-spring seasons.) You may realize that some of these sheaths are showing signs of yellowing. This is normal. Autumn’s more pronounced temperature fluctuation can lead to water condensation inside the sheath, hastening the normal process of aging, so yellowing sheaths can be left on the plant so long before they must be carefully got rid of to save the bud primordia within from being harmed. Water condensation left unchecked can rot the bud primordia. The sheaths can be safely taken away by slitting open and peeling down toward the pseudobulb.

Cool-Growing Orchids

One can nearly hear a sigh of relief from all of the cool-growers, from masdevallias to odontoglossums. When day temperatures decline, one can see an easy to notice improvement in these plants. Shorter days and lower light levels do not seem to bother them. Repot before winter comes.

Cymbidium

Eventually we begin earnestly in the main cymbidium season. Cymbidium ensifolium can give some early and fragrant hybrids, but it is now that the largest part of the crop will be flowering. The season continues for about seven months, adding color to any collection. Very small varieties will be great for the next three to four months. There are three important things to do: stake inflorescences ramrod straight for the best presentation, watch out for slugs and snails (particularly just after a rain), and fertilize with a mild balanced formula regularly.

Oncidium crispum Complex

This is the season to shine for plants in Oncidium section crispum from Brazil . Extremely vigorous hybrids have wide varieties of markings dominated with chestnut and brown and butter yellow. Give the plants intense light to produce strong upright inflorescences. The pseudobulbs should be plump, so do not let the plants dry out while they are in full bloom. Later, plants will enter an inactive period.

Paphiopedilum

The flowering season for the “toads” or “bulldog” paphs is just having started to happen. These cannot be grown everywhere, but where cooler summer nights allow their growth, there is no longer-lasting or more unusual and interesting display than these. Paphiopedilums are, usually, not heavy feeders, and it is particularly important with this type to lower nitrogen levels now for the best flowering and spike length. Be very careful to notice for water accumulating in the growth around the sheath, or for the late-season warm spell, either of which can lead to the sheath’s rotting. As the spikes come out, do not change the orientation of the plant toward the light, because this can lead to a bended or twisted spike

While paphiopedilums seldom like to dry out completely, water needs are significantly lowered beginning now. Overwatering at this time of year can quickly lead to root rot or erwinia troubles. Now is the time to practice good hygienic practices in your greenhouse or growing areas, because pest and disease problems have a way of multiplying quickly in the darker and more crowded environments that usually characterize the winter growing area. With paphiopedilums, especially, “cleanliness is very close to godliness” and if the growing area is full of old foliage, weeds and dying flowers, keeping the plants alive and flowering will be very closely to impossible.

Phalaenopsis

Shortening days and cooler nights are the signs for inflorescence initiation in phalaenopsis. In more northern weather conditions, or on the west coast, growers have already begun to see the early inflorescences which may be ready for Christmas. In the eastern parts, nights in the greenhouse will now be in the low to mid 60s, counting on the thermostat setting, so the first of our phalaenopsis will not begin to bloom till Valentine’s Day no earlier than the time.

A decrease in nitrogen levels will go a long way to giving the best possible spiking, as will a boost in potassium and phosphorus. In other words, a “bloom booster”-type fertilizer is definitely signed in the next few months. Disease and pest troubles are best dealt with now, especially as mealybugs hide in the bracts and flower buds. Once they have established themselves, they are difficult to completely get rid of, and flower damage or crippling results. Possible disease problems can be dealt with by the using a copper-based compound to control/alleviate rot troubles before they begin. There is nothing more annoyed and upset than to have shepherded your plants through a growing season, only to have them decline before your eyes.

Vandaceous Genera

While the general decline in temperatures is beneficial to cool-growing orchids, it is not true for vandaceous plants. The only cold-hardy member is Neofinetia falcata. Orient your plants in such a way to take advantage of light as much as possible. This can be troublesome in northern latitudes. lower watering and feeding schedules.