Bromeliads easy to grow in various simulated settings

June 24, 2004

AMY GILNER

Victoria County Master Gardener

Several recent articles in this column have referenced heat and drought tolerant plants - and recommended irrigation practices for both turfgrass and xeriscaped landscapes.

With summer officially here this week, some plant varieties will need protection from direct sunlight to prevent their leaves from scorching, or in other cases, to prevent foliage from fading. Others still require bright light for vivid color, but must be kept evenly moist. In any case, careful watering practices are essential for healthy plants in the heat of the summer.

Such is the case for varieties of bromeliads. Warm and humid conditions in the Victoria area provide a natural environment for bromeliad plants that, as members of the bromeliaceae family, number more than 2,700 species in approximately 56 genera. Most bromeliads are used for ornamental purposes, with the only member of the family that can be used for food being the pineapple.

Bromeliads grow wild in the southern United States and may be found in Central and South America as well as in the West Indies. They are colorful, often variegated with several colors streaking the leaves, and have gorgeous flower stalks. They are easy to grow outdoors in warm climates like Victoria, but can also be grown in a greenhouse or indoors.

Bromeliads are found mainly in rain forests, but may also be found in mountainous and semi-arid areas. A few species grow by the seashore and in marshes. Most bromeliads are epiphytes (a plant that depends on another for mechanical support but not for nutrients) and grow well in tropical climates. You will find them attached to rocks and trees with very little soil around their roots. Some, however, are terrestrial and grow in soil. My personal favorite is Neoregelia carolinae 'tricolor' with green, red and pink variegated leaves.

All bromeliads are composed of a spiral arrangement of leaves called a rosette. The number of degrees between leaves varies with the species. This causes the plant to grow in a flattened form with its leaves lined up in a single plane. The bases of its leaves may overlap to form a water reservoir. This is called the central cup. Bromeliads vary in size from the Bromelia balansae, which is a small low growing plant, to the Puya berteroniana, which is a tree-like species and can grow up to 15 feet tall. Rosettes are generally erect and may consist of brightly colored and/or variegated leaves. The leaves can be toothed or spiny, which assists the plant in absorbing water. Other bromeliads, such as the air plant (Tillandsia), have scales covering their leaves to help them retain and absorb moisture and nutrients from the environment. Some bromeliads, like Guzmania and Aechmea, form a cup in the center of the rosette, which catches and retains water and nutrients.

Bright flower stalks may grow out of the center of the rosettes or grow low in the center cup. As members of the monocotyledon family, bromeliads have a single seed leaf, leaves with veins that run parallel to the length of the leaf, and flower parts that are in groups of three. A bromeliad flowers only once and thereafter the rosette dies. New plants, called pups, grow from dormant buds at the base of the plant or on the rhizomes or roots. Once the pups are large enough, they can be used for propagation.

Bromeliads are easy to grow if you simulate their natural growing conditions. In Victoria's climate, which is both warm and humid, bromeliads grow well outdoors as long as they have some protection from heat, direct sunlight and rain. One of mine hangs from the branches of a crepe myrtle and it benefits from the dappled shade. The crepe myrtle acts like an umbrella protecting the bromeliad, preventing it from becoming completely soaked by the rainfall. Most epiphytic bromeliads need partial shade outdoors and in the greenhouse because bright light can make the foliage fade. However, the color of some terrestrial bromeliads improves with full light.

Epiphytes can be attached to a tree trunk or a branch with wire. They can also be attached to cork bark and tree fern slabs and poles. You should cover the base of the plant or roots with sphagnum moss to retain moisture and this helps to conceal the wire as well. Water sparingly with rainwater if available, and mist the plant in very hot weather. I suggest growing bromeliads indoors in a container in a mixture of equal parts shredded peat moss and granulated bark. Mist the peat/bark mixture daily and keep the cup full of water. Both epiphytes and terrestrials may be grown outdoors in a pot in a coarse fertile soil that drains well, such as cactus or succulent mix.

Terrestrials and rock dwellers may be grown indoors in a mixture of one part peat or coconut fiber, one part leaf mold, and three parts coarse sand or gravel. Water sparingly, allowing the planting medium to dry partially between watering.

For indoor epiphytic bromeliads, mist an orchid foliar fertilizer on the plant during the growing season, typically spring through summer, at one-quarter strength every four or five weeks. No fertilizer is needed during the winter months when the plant is dormant. For terrestrials and rock dwellers, use one-half strength low nitrogen liquid fertilizer every three or four weeks when watering. Again, no fertilizer is needed during the winter months or dormant period. For all bromeliads grown outdoors, no fertilizer is necessary because the plant will obtain its nutrients from the air and rain.

Bromeliads may be propagated when the new plant is fully developed into the rosette shape. Divide the new plant at the base of the mature plant, and pot it up in a mixture of equal parts of shredded peat, leaf mold and coarse sand or gravel. Keep the medium moist but not wet until new growth appears. Pups can also be mounted on bark or cork, but make sure the cut end is well covered with sphagnum moss and is kept moist. The lower leaves should be filled with water as well.

Bromeliads are inexpensive, easy to propagate and grow, and will provide you with colorful and unique foliage and flowers for years to come.

Are you interested in learning more about plants and landscaping, including other area tropicals, perennials, roses, water gardening plants, native plants - and more? Then let your knowledge base blossom in training as a Texas Master Gardener. Aug. 2 is the registration deadline for the new fall training class, which will run Aug. 12 through Dec. 9 in Victoria County. Look for brochures in area garden centers or call the Victoria County Extension office at 361-575-4581 for more information.