Grow tropical beauties without a greenhouse

Flower & Garden Magazine, March-April, 1997 by Ruth Shaw Earnst

You needn't re-create jungle conditions to grow beautiful tropical plants that appear as flamboyant and cheerful inside the house as they do in a Brazilian rainforest.

Having a greenhouse has always been a temptation to me. I've resisted because I know that if I had one I would take up residence there along with the plants and neglect everything else in my life. Unwilling to forgo houseplants with tropical origins, however, I decided to experiment with these greenhouse dwellers to see which would thrive in windowsill conditions. It was a challenging project that resulted in gratifying success.

My first choice was anthurium, a plant whose stunning flowers fascinated me. Even though I had heard that it doesn't always adapt well to the average dry conditions in the home, I was determined to give it a try. Anthuriums are native to South and Central America and are kin to callas, caladiums, spathiphyllums and others in the arum family (Araceae). More than 500 species of anthurium exist, but few are suitable as houseplants.

Of these, Anthurium scherzeranum, called pigtail flower or flameflower, is most successfully grown and most readily available. The lance-shaped, dark green leaves reach 8 to 10 inches in length on a mature plant and are attractive even when the plant is not blooming. But the real excitement is the flower, consisting of a petal-shaped spathe, generally orange-red in color (less commonly in shades of salmon, rose, white or white with pink spots), and the curly spadix rising in front of it, which bears the tiny true flowers and gives the plant its common name. These vivid inflorescences last a long time on the plant. A mature, happy anthurium will send up blooms for most of the year, rest for a couple of months, then start flowering again.

Success with anthuriums relies on proper soil, moisture (humidity as well as water), warmth and light. The potting soil should be fibrous, organic and peaty, with some fir bark. Keep it moist but not waterlogged, and never let the plant sit in water or dry out completely. Provide humidity with a daily misting and by setting the pot on a tray of pebbles or lava rock kept constantly wet. As water evaporates from the tray, the air surrounding the leaves remains humid.

Warmth is a necessity; anthuriums do best in temperatures above 60 degrees and respond well to very high temperatures. They're not fussy about light, thriving indoors in medium to bright light from an east window and outdoors in filtered sun to partial shade. Direct sun must be avoided, as it will burn the leaves.

As the plant grows, it develops multiple crowns that often send down aerial roots. When the pot gets overcrowded, remove the plant in spring and divide it carefully, making sure each division has a crown with roots and leaves. Replant individually in small pots in the recommended soil mixture.

Give anthuriums a light application of liquid houseplant fertilizer every two to three weeks during their active growth period.

My anthurium, along with other tropical houseplants, sits on a pebble tray in an east window and summers outdoors on my terrace beneath a maple tree that filters the sunlight. A small, young plant to begin with, it needed to grow larger and become well acclimated before it bloomed. It took a year and a half until the plant began to produce its exotic flowers, but it has continued, almost without a pause, ever since.

Calathea, of the Marantaceae family, is native to tropical South America and is highly prized as a houseplant because of its handsomely patterned foliage. There are numerous species of this plant, whose common name is prayer plant. The one I chose to grow is Calathea ornata `Roseo-lineata,' which bears stiff, shiny, dark green leaves up to 8 inches long. They have pale pink stripes on top and a maroon or burgundy underside. Calathea's leaves begin to point upward, leaving no doubt as to the origin of its common name, as the sun sets and night approaches.

Native to tropical jungles, calatheas are similar to anthuriums in their preference of moist, organic soil and bright, indirect light. They also share the anthuriums' requirements for warmth, humidity and light feeding during the growing season.

Calatheas are slow growers that won't require division for several years. When the pot becomes overcrowded with new shoots, remove the plant in spring and divide it into sections with plenty of roots and some leaves on each. Replant these separately in 3- to 4-inch pots.

My calathea spends the summer in the dappled fight under my maple tree. When the weather is hot and dry, a fine spray with the garden hose is gratefully accepted.

Maranta is closely related to calathea and is also called prayer plant. There are many varieties of this native to the tropical forests of Brazil. I chose the one with the impressive name of Maranta leuconeura erythroneura because I liked its striking coloring and lush growth. The dark green oval leaves, 4 to 5 inches long when mature, have lighter green splotches along the midrib. Both midrib and lateral veins are a bright rosy red. The underside of the leaf is an intense purplish red.