Hardy Hibiscus Plant and Tree

Question: A hibiscus plant is one of the plants we brought back from our Hawaiian vacation. Can Hibiscus be grown indoors? We also saw small hibiscus trees that were interesting but like the bush type much better. Can hibiscus be grown outdoors in a pot on a patio or deck? Courtney, Nashville, Tennessee

Answer: Hawaii and Hibiscus – picturesque words that denote an exotic, tropical climate. The hibiscus (hy-BIS-kus) lends itself beautifully to pot culture, and because there is no dormant season for the potted plant, it may be kept in bloom the year around. George Washington ordered hibiscus from Philadelphia nurseryman John Bartram in 1792. These plants had single, red flowers, similar to the present day variety.

A bushy plant, three feet tall, will thrive in a six to eight inch pot. The soil must afford perfect drainage. The growing medium must be rich and humusy. Soil that grows good African violets is usually satisfactory for hibiscus. Here is a recipe for hibiscus potting soil: equal parts garden loam, peat moss, fine bark and sand.

Hibiscus use large amounts of water, and watering may be required every day. This free use of water leaches out the food in the soil and fertilizing is necessary every week. A plant food that has too much nitrogen will give too much foliage and not enough flowers – a well-balanced food should give blossoms that are well colored, quite large, and in normal quantity.

Lots of Sunshine

Plenty of sunshine is necessary to make the plant grow sturdy and to produce blooms. To insure good branching, the plants should be pinched when small. If the pinching is done just above an outside bud, the new growth will branch out into a desirable bush. The flowers are borne on the young wood, and a heavy pruning is in order every year so that plenty of new growth can develop without the bush becoming too large for indoor growing.

Hibiscus thrive under fluorescent light culture. The tubes are placed so that they do not quite touch the top foliage of the plant. Hibiscus matensis, a species with variegated pink, silver and green leaves, has been known to thrive and flower all winter under fluorescent lights. The fluorescent unit can be made of two 48-watt tubes. Given much humidity and 12 to 15 hours daily illumination, they all do well under the lights.

Growing temperatures should range from 60 to 65 at night to 75 during the daytime.

Hibiscus Propagation

Hibiscus are easily propagated by cuttings which may be taken at any time of the year when the plant is in good growth. These will root in water, or they may be started in a moist mixture of peat moss and sand, or in vermiculite. When roots form, they should be potted into regular soil. Cuttings rooted under fluorescent lights can be potted in six weeks’ time, and flowered in less than a year.

The seeds are large enough to be easily handled, and blossoms come in about 18 months. Seeds can be planted in vermiculite, peat moss, or sand – hest of all, a mixture of the three. It is wise to supply an individual pot for each seed. This saves transplanting shock later on. To set seeds on a plant, simply place loose pollen from one bloom into the little pads of stigma at the top of the pistular column of another bloom. All varieties are not fertile, but a little experimenting will teach which ones will set seed.

Hibiscus thrive outdoors in the summer. When you put it out in May or June, thin out weak wood and prune to make the bush as shapely as possible. Keep the plant in partial shade.

It is said that the flowers can be rubbed on the shoes in place of blacking when one needs a shine. The hibiscus is of the shoe-flower family, and is closely related to hollyhocks, the rose of Sharon, okra and cotton. The flowers in the wild afford a red dye that is commonly used in cookery coloring.

If you order a plant that comes in a small pot and the leaves are rather banged and bruised, cut the top back partially to give the roots a momentary rest and then a chance to grow. A plant without a good root system cannot be expected to continue to produce a floriferous plant.

If grafting fascinates you, five or six varieties of hibiscus may be grafted onto one root stock. Hibiscus pests are not many – aphids, red spiders and mealybugs are about the worst that attack. Aphids can be licked with one of the house plant sprays; red spiders detest high humidity which hibiscus need to thrive, and mealy-bugs can be wiped out with a spray, or by dabbing them with alcohol. Weekly spraying with tepid water keeps the foliage clean and attractive.

by E McDonald

Related Articles Of Interest:

• Fluorescent Grow Lights and the Basement Garden
• Do You Know How Long To Leave The Lights On Indoors?
• Types of Artificial Grow Lights
• Selecting Grow Lights For Indoor Plants