PLANTS IN THE house can provide a lot of pleasure if given proper care. Foliage plants may be best for the home because they can survive environmental conditions that are unfavorable to many other kinds.

Foliage plants may have flowers, but they will be secondary.

Most foliage plants are of tropical origin. They were grown in greenhouses in many areas of the United States in the early 1800s, but were not grown commercially in Florida until about 1925.

Commercial foliage plant production is now an important Florida agricultural industry, millions of Florida plants are sold annually with sales in many foreign countries as well as the United States, and Florida is the acknowledged "Foliage Capital of the World."

Two of the most important causes of failure with most foliage plants are improper watering and insufficient light, according to specialists. Temperature is third.

Some people believe that small amounts of water should be applied frequently because they have read or been told that the soil must be kept uniformly moist or damp.

The frequency of watering each kind of plant will vary. Even two plants of the same kind may have different water needs because of different environments.

Containers with drainage holes should be placed in a saucer and sufficient water applied at each wa-See HOUSE PLANTS, Page 3, Col. 3 HOUSE PLANTS, From Page 1 tering until excess water drains out the bottom. This water should be discarded because pots should not be allowed to stand in water for any length of time.

Containers without drainage holes should have a layer of coarse gravel in the bottom to allow space for excess water. After watering, a good way to check them is to lay them on their sides in the sink and see if much water runs out.

"Foliage plants are adapted to regions where soil is moist, but not continually saturated with water," says Dr. Charles A. Conover, chief of the Florida Agricultural Research Center, Apopka, which devotes itself exclusively to house plant problems. "Never allow soils to become completely dry between waterings, and what watering apply enough water to thoroughly wet the entire soil ball. This is most important," he says.

"The importance of adequate light cannot be overemphasized," says Conover. "Without ample light, photosynthetic processes are inadequate to produce sufficient food for plant growth. Thus the plant must utilize stored food, and deterioration of plant quality occurs until reserves are consumed and death occurs.

"Most foliage plants will survive for 12 months under a light level of 50 foot-candles for 12 to 15 hours each 24 hours (a foot-candle is the amount of light produced by one candle at a distance of one foot).

"Light intensity controls to a considerable degree the rate of food production (photosynthesis). Light duration is also important, since the total number of foot-candles of light received is a product of intensity and duration.

"The longer the plant is lighted, the more food produced and, therefore, when plants are grown in low-light areas they should be lighted for longer periods to counteract low light intensity.

"Specialty fluorescent lamps have been designed to produce the light quality necessary for plants. Supplemental lighting may be applied anytime during the day or night.

"The most desirable temperature range for foliage plants is 70 to 75 during the day and 65 to 70 at night. In general, plants require a lower night temperature than day temperature, but this is not critical for foliage plants. Temperatures below 60 can be damaging."

Q. For the first time I have seen a flower arrangement with poinsettia bracts in it. It looked stunning. Do they need some special treatment?

A. Cut poinsettias can be used in all sorts of design work. They will last all through the Christmas season -- normally they will last 14 days at room temperature after being cut, if the green leaves are removed (not the colored bracts). If the leaves are necessary for the design, place the cut stems in boiling water for 30 seconds or singe over a flame.

Q. I was given an arrangement of anthuriums for Christmas. It is a beautiful, beautiful flower. Can they be grown in the home with any success?

A. The anthurium (flamingo flower) requires so saturated an atmosphere that it is almost impossible to grow it successfully in the home. Most kinds originate in Columbia where the average rainfall is 390 inches per year.