Q: Our rhubarb is crowded and needs to be divided. When is the best time to do it?

A: Rhubarb usually needs to be divided when it's four or five years old. The best time to do it is early spring or late fall when the plants are dormant. The crowns may be cut into as many pieces as there buds. A piece of root with one strong bud will usually produce a good plant in one season. If you want to keep the rhubarb growing where it is, division can be accomplished by spading away parts of the crown.

Q: Will pansies grow in a place where they get light shade part of the time and rather heavy shade the rest of the day?

A: Pansies need a bright sunny location at least half of the day. Too much shade results in spindly plants with flew flowers. They're shallow rooted and shouldn't be planted where the soil may become quite dry.

Q: When is the best time to plant asparagus?

A: Early spring is the usual time, when garden centers have the roots available for sale and mail order places ship the roots.

Q: Will gasoline kill wild onions and wild garlic without harming plants or grass?

A: Gasoline should never be used to control weeds around the home or garden. It can harm many beneficial plants and the soil.

Q: Last year almost all of our apples were ruined: many fell from the tree before they were ripe and most of the others had worms in them. What can we do to get good apples?

A: Many gardeners do not spray and some get fairly good fruit some years. Generally, there's little chance of getting good apples without spraying several times during the growing season to protect them from insects. Most commerical growers spray 12 times or more each year. Use an all-purpose apple spray.

Q: What variety of sunflower do you recommend for birds?

A: Mammoth is one of the best for bird seed. It reaches a height of about 10 feet and stalks are topped with huge golden flowers eight to ten inches across. The heads mature and are ready for harvest about 80 days after sowing. After this, cover them with cheesecloth to keep birds out. Cut off heads when they are plump and fairly hard and spread in a warm, airy palce to dry. Shell when they are throughly dry and store. Mammoth is listed in the Burpee Seed Catalog, Warminster, Pa. 18991 which will be sent free on request.

Q: Is there an effective way to control slugs in my vegetable garden without using poisonous chemicals?

A: Researchers at the Beltsville Agricultural Research Center found that during a four-day test, beer placed in a shallow pan caught more than 300 slugs. They also found that stale beer works as well as fresh beer. When the researchers performed autopsies on the dead slugs, they found their stomachs loaded with beer.

Q: Should a newly planted tree which is five feet tall be staked?

A: Do not stake the tree unless it is likely the roots will be disturbed when the wind is blowing hard, loosening them in the soil. A young tree with its top free to move usually becomes a stronger tree. Researchers found that trees left unstaked develop thicker trunks and stronger roots and those staked for two years were blown down soon after the stakes were removed.

Q: We have a large old apple tree with a condition we are told is a canker and the remedy is to prune it away. Do you agree with this?

A: A tree canker is a diseased or depressed area on bark or branch. Research by Hudson Valley Laboratory, Geneva, N.Y., has shown that 40 percent of cankers on apple trees result from leaving stubs when pruning. Properly made pruning cuts soon begin to heal whereas improper ones heal very slowly if at all. These wounds provide entry for the infecting fungus. Usually the remedy for cankers is to remove them by pruning making the cut back to healthy wood.

Q: I've been told earthworms will improve my garden soil.Where can I buy them?

A: If you have no earthworms at present, bringing them in would not help because they would not stay. Improve the soil by adding organic matter and other essentials, and you'll soon have plenty of them. If you have good soil you can't keep earthworms away.