Daniel Gill, Merrill, Thomas A. | 8/30/2007 1:58:13 AM
By Dan Gill
LSU AgCenter Horticulturist
Bromeliads are a beautiful group of tropical plants. With their many shapes and colors and their ease of culture, once you have one bromeliad you are likely to want more.
But even one or two plants will make an excellent addition to your potted plant collection, since you can find bromeliads that have colorful foliage, beautiful flowers or both. Better yet, they are easy to grow.
Bromeliads main requirements are sufficient light, proper watering and good air circulation. Indoors, bromeliads thrive in an east, west or south window that receives plenty of light. Outside, these plants generally prefer a semi-shaded location that receives morning sun but is shaded from the intense light of midday and afternoon or a location that receives dappled light through the day. Those with plain, green leaves often require the most shade, and those with silvery or gray foliage generally will tolerate the most sun.
Although it is excellent to "summer" your bromeliads outside when temperatures are higher, the plants must be brought inside and protected during freezing weather.
Most bromeliads are grown in pots of well-drained potting mix. You won’t have to repot your newly purchased blooming bromeliad into a larger container. The container you buy it in will be big enough. If you obtain a young plant that still has a lot of growing to do, you will need to repot it into a larger container as it outgrows the one it’s in. When you do, use a light potting soil with some extra perlite, or make your own with equal parts of sphagnum peat moss, medium-grade horticultural perlite and fine fir bark.
Because most bromeliads have rather limited root systems, they generally are grown in pots that are somewhat small for the size of the plant. Clay or plastic pots are equally satisfactory as long as they have drainage holes. Clay pots are more stable because of their weight and may be better for plants that tend to be top heavy. A layer of pea gravel in the bottom of the pot also can add stability (although, contrary to popular belief, gravel in the bottom of the pot does not help drainage).
The mix should not be kept constantly wet, since bromeliads do best when allowed to dry slightly between waterings. Many species of bromeliads are able to hold considerable reserves of water in the vase-like center of the plant. This should generally be kept full of water, because the leaves themselves can absorb water.
Although we generally grow bromeliads in containers for the sake of convenience, in nature these plants are typically epiphytes – plants that grow upon other plants (generally trees) but are not parasites. The water-holding vase-like shape of many bromeliads is an adaptation to their tree-dwelling nature. Without soil to retain moisture, you can see how the reserved water held by the leaves would help the plant survive between rains. This trapped water also is very important to many animals that live in the trees.
Spanish moss, our native epiphytic bromeliad, does not produce a cup but does absorb all of the water and nutrients it needs through its leaves. The leaves are covered by gray scales, which give this plant its characteristic color and trap water against the leaves until it can be absorbed. I’m often asked if Spanish moss growing in a tree will somehow injure the tree. Spanish moss makes all of its own food and derives the water and minerals it needs from rain, so it is harmless to the tree it is growing on.
Because of their natural ability to grow on trees, you may purchase bromeliads mounted on a piece of driftwood or other material. These plants are a little more trouble to maintain than potted bromeliads and require more frequent watering – generally best done at the sink if the plants are being grown indoors. Keep gray-leaved bromeliads well misted and the cups of others filled with water. Even though bromeliads mounted this way are a little more trouble, they are worth the extra effort because mounted bromeliads are strikingly beautiful.
Bromeliads that produce attractive flowers are often purchased in bloom. The flower spikes are exotic and beautiful and usually stay attractive for an extended period. Some types, such as Neoregelia, do not produce especially showy flowers, but the foliage in the center of the plant turns a brilliant color when they bloom. Indeed, for most bromeliads, it is not the flowers that provide the primary show but the colorful bracts or modified leaves that accompany the flowers that add much to the display.
It is important to know that after blooming a bromeliad plant will never grow or bloom again. They go into a gradual decline and eventually die. Before they do, however, they produce one to several offshoots from their base called "pups."
These young plants can be separated from the original plant when they are about one-third its size. This is really easy, and since most bromeliads produce more than one pup, you will have extra plants to add to your collection, share with friends or trade for other plants.
If you like, you can even just cut off the original plant when it is no longer attractive and allow the pups to grow together in the original pot – although this is not always the best way to handle them. Some bromeliads look great grown in a cluster, while others are more attractive grown singly.
Get It Growing is a weekly feature on home lawn and garden topics prepared by experts in the LSU AgCenter. For more information on such topics, contact your parish LSU AgCenter Extension office or visit our Web site at www.lsuagcenter.com. A wide range of publications and a variety of other resources are available.