Poinsettia and Other Indoor Plant Care
It’s easy to see how the poinsettia has become associated with Christmas. Its red and green foliage ties in well with the colors of the season, and of course they naturally bloom at this time of year. There are a few things to consider to maximize the life of the plant. First, most retailers ship plants in boxes from long distances. Often these plants display a droopy appearance, as if they need water. This condition, called epinasty, results from a buildup of ethylene gas (produced by the plants themselves) from being boxed or sleeved too long. This won’t happen with Stan’s Homegrown Poinsettias, which are only “shipped” a few hundred feet, from our own production greenhouses!
By the way, the red or other colored “flowers” aren’t flowers at all, but modified leaves called bracts. The actual flower is an insignificant yellow structure in the center of the bracts. The freshest poinsettias will have these flowers intact, though even after they drop, the bracts will stay on until April or May- or longer!
Poinsettias and other holiday blooming plants last longest when grown in a brightly lit window, though they will tolerate other locations away from hot or cold drafts. The most common cultural problem is root injury caused by being allowed to sit in water, or by being allowed to dry out too much between waterings. Ideally, these plants should be watered when the soil surface begins to dry. Use lukewarm or room-temperature water and remove any decorative foil or pot covers before watering. Allow to drip-dry over a sink before returning to its pot cover. Typical home temperatures are fine, though poinsettias in particular last longer when kept in the high 50s to low 60s. After the colored bracts fade or drop they can be cut back by one half and grown as a house plant. Poinsettias can be reflowered with some effort - but that process is a topic for another column. Suffice it to say, it's a fair amount of effort for often disappointing results, as many of our customers have noted.
Other Plants/ Amaryllis. Many of our customers have had difficulty in reblooming amaryllis in their second year. Like other bulb plants, care after the bloom is critical. It's essential that you not quit watering and feeding after blooms fall- in fact, it's more important to provide good light, water and feed - since this is the period when the bulb stores nutrients for its next bloom cycle. Failure to maintain this regimen until foliage dies naturally produces leaves but no flowers.
Holiday cactus- Christmas and Thanksgiving cactus- will experience a resting period after bloom; cut back on watering and place outdoors in late May/ early June.
Norfolk Island pines like bright light indoors. Since they are subtropicals, they like temperatures cooler-as low as 50o- than most other house plants. They also require high humidity (see below). Norfolk pines have a weak root system, so avoid repotting until absolutely necessary. They also don’t produce new branches, so avoid pruning and rotate the plants regularly to prevent branch loss.
House Plants in general may suffer from low light and humidity. If possible, group your plants near your brightest or biggest window (don't worry about them getting too much light in a southern window: it's Erie- it's winter- it ain't gonna happen, at least not until spring.) This not only allows them to benefit from the available light, but their combined transpiration will create a more humid microclimate. Other marginally effective means of providing humidity include misting, placing on trays of wet gravel and lowering room temperature. Remember that they won't need as frequent watering as they did in summer; watering as illustrated in the poinsettia section works well.