REPOTTING

Visit: "Conifer Wildlife Habitat: Arboretum de Concord - Conifers from around the World grown in Michigan"

The decision to divide or just to repot will also depend on the type of plant in question. The Pink Quill (Tillandsia cyanea) is not much bigger when it has four or five growths than when it has only one and I would leave the clump undivided in the hope of getting several blooming spikes at once, a much more striking effect than a single spike provides. Bromeliads with long, slender tubes such as Billbergia look better when the pot is full of growths and certainly the effect is much more spectacular when the plants bloom. (Don't worry about the plant being "potbound": epiphytic bromeliads enjoy being under potted!) I like to leave the green-leaved Vrieseas in their pots after they bloom.

   A plant will produce two or three pups which soon completely hide the mother as she gradually fades away. The plant does not have to be repotted but one must bear in mind that when the pups are mature, the plant will be two or three times larger than the original. The pups usually bloom at the same time. The vase-type bromeliads, with their flaring rosettes - Silver Vase (Aechmea fasciata) and Neoregelias, for example, develop better symmetry if grown singly. Indeed, they are often rather large plants and quickly become unwieldy if there is more than one growth in the pot.

   You may not need to repot if there is room for new pups and the planting medium still drains well. If you want to increase the number of pups without repotting, separate the pup from the mother plant as soon as it shows roots at its base or has attained 2/3 the size of the mother plant. This is easily done by cutting through the stolon (stem) connecting mother to pup. Neither plant is disturbed in the process. If there is no stolon and the pup grows tight against the mother, separation is trickier: one must be careful not to injure the base of the pup. Separating the pups from the mother will stimulate the mother to produce more pups, a process which can continue until the mother finally has no leaves left. Sometimes in repotting a plant we find the roots partially or even completely rotted away, usually the result of water collecting in the pot instead of freely draining out. If the plant itself shows no rot, loss of roots is not a problem. The plant can be placed in new medium, staked or otherwise firmly anchored, and it will soon grow new roots.

   While many different mixtures are used for growing bromeliads, a good and easy-to-mix medium is a mixture of Canadian peat moss with perlite. Use enough perlite (I/4 to 1/3) to guarantee that, as the peat compacts over time, drainage will remain fast and complete. I like to add fine cypress mulch to my mixture to help keep the plants in place until they have developed a root system.

Should you fertilize? Bromeliads do remarkably well without the use of fertilizer-after all, in their natural setting they do not get a large supply of nutrients. But as houseplants they do not get the nutrients brought by wind and rain in the natural setting. So it makes sense to fertilize and in general they respond well to fertilizing. Application should be only half the dosage recommended on the label. In the case of Billbergias and Neoregelias with highly colored leaves, fertilizing should be very modest since it tends to mute the color and markings, and may lead to ungainly oversized leaves, particularly if available light is not strong (part sun). If the nitrogen in the fertilizer is ammoniacal, as in Schultz Bloom Plus or fertilizers designed specifically for bromeliads, the nitrogen will be available through the leaf surfaces. The plant will then benefit from being misted or drenched with water containing the fertilizer.

Bringing them back into the house:
All too soon we will have to bring back in any bromeliads we are summering outside. Back in, where there isn't enough light, enough humidity, and above all, enough room. We always manage somehow but of course it's nice to put it off as long as possible. How long is that? Do they need a transition to house conditions? I once brought a non-hardy azalea into the house in November just before a killing frost. Next day it had turned to paper. Fortunately for us procrastinators, bromeliads are much hardier. Many of them can take a bit of frost without damage and the transition to the lower humidity in the house does not seem to affect them. At temperatures below 50 they should of course be kept drier to avoid rot. There are many tales of heroic survival in temperatures to which they should have succumbed. In general, though, it is a good idea to bring them in when the temperatures begin to fall below 50°F. If you have too many, you might want to experiment and see how much winter they can take. Please report your findings to us.