Cindy Leveet of Falls Church writes:

I have several questions to ask.

1. The fronds of my Areca palms have been turning brown and dying ever since I've had them. Misting seems to help but doesn't alleviate the problem. I water once a week. They could be slightly potbound. What causes this drying out?

2. How often should I water my Yucca - not a woody-stem type? Would over-watering result in yellowing of lower leaves?

3. How should gibberellic acid be applied to most house plants, and how often?

4. Can Jersualem cherry plants be grown from their seeds?

Areca palm. Palms require plentiful water, sometimes as much as two or three soakings a week. Perhaps a once-a-week watering is insufficient for the size of your plants; small feeding roots in the bottom of the pots may have dried up. Good drainage is important. Placing the pots on pebble trays with water will help to increase the humidity around the plants.

Yucca. There is no hard and fast rule for watering any of your houseplants. You need to develop a sense of the feel of the soil. In this case the yellowing of the leaves may be due to poor drainage and a water-logged condition in the bottom of the pot.

Gibberellins. The gibberellins are chemicals which stimulate many developmental processes and counteract others. Horticulturally, they are best known for their production of larger, earlier flowers on camellias. These particular plant growth regulators are not applied to houseplants.

Jerusalem cherry. Jerusalem cherries are grown from seed contained in the "cherries." When the fruit withers, remove it from the plant and clean the pulp from the seeds. Seeds can be planted at once, or stored dry in an air-tight container in a cool place until spring, for starting plants indoors or for planting out in the garden.

John W. James of Washington, in a long letter, describes the condition of his Christmas poinsettia - losing old leaves, producing new shoots at the bottom, some old leaves looking healthy. The questions are: why shouldn't there be more leaves coming from the tops of the stalks; could the falling leaves be caused by too much or too little water; and is the plant progressing in a normal manner?

Your poinsettia is progressing in a normal manner. Be sure to give it a bright warm place; water it when the soil surface feels dry and be sure it drains well. When danger of frost has passed (mid-May), repot the plant, set it outdoors in a lightly shaded place, feed it monthly with a liquid houseplant fertilizer. During the summer, until about mid-August, you can prune the plant periodically to encourage branching; the result will be a bushy green foliage plant of some beauty. If you want it to produce red flowers (bracts) next winter, you must arrange to provide absolute, uninterrupted darkness for 14 to 16 hours each day from about September 20 to the middle of December in order for it to develop buds which will produce the flowers.

Questions about indoor gardening can be addressed to Jane Steffey in care of The Weekly, The Washington Post, 1150 15th St. NW, Washington, D.C., 20071. Please include your name and telephone number.