TRANSISTOR radios, playing in the berry patch, may save your crop from the birds. The feathered foragers appreciate neither rock nor classical music, and hate all-news stations. If you develop radio-proof birds, other kinds of commercial noisemakers, including bird distress calls, are available.

This advice comes from the newly published "The Berry Book -- The Illustrated Home Gardener's Guide to Growing and Using Over 50 Kinds and 500 Varieties of Berries," by Robert Hendrickson (Doubleday, 259 printed pages, $14.95). Your bookstore can order it for you if it does not have it in stock.

Birds of many feathers are probably the worst pests you'll encounter in raising berries, according to Hendrickson, though they'll attract many beautiful species you wouldn't have seen otherwise.

To prevent birds from devouring the entire crop, he suggests, try any of the following methods, in addition to the time-honored scarecrow:

Pieces of rope or garden hose placed at strategic sites may be mistaken for snakes by birds, who then keep their distance.

White string wrapped around bushes looks like spider webs to birds and scares them off.

Broken mirrors or aluminum pie plates strung on bushes often frightens birds away.

"The Berry Book" also tells how to grow berries at home or gather them in the wild, how to propagate wild plants and where to buy berry plants.

Lucious fully-ripe strawberries, raspberries, blackberries and blueberries are easy to grow and there is a good reason for growing them. Those purchased at the market are not nearly as nice as those harvested when fully ripe.

For example, strawberries for the market are picked when they turn whitish. They turn red after being picked but never gain in flavor. Raspberries are seldom seen in the market because they spoil so quickly. Blackberries are not ripe when they first turn black; they should be harvested when they are sweet and ready to drop off at the slightest touch. Blueberries should be allowed to stay on the plant for at least one week after they turn blue. Ripe berries will come loose easily and drop off into your hand.

"Home-grown berries can be raised by anyone with a small patch of ground in the backyard (or by city gardeners on a terrace) . . . They are not specialty items for expert gareners alone, as so many people believe," the author writes.

". . . Berries can be planted in space-saving ways in the back, front, and on the sides of the house, and they cost practically nothing to care for. These delicious fruits often aren't obtainable anywhere unless they are home-grown, or if available, can cost as much as four dollars a pint to buy."

Q. I try every year to grow watermelons but all I get is a lot of vine. I keep them well fertilized and watered but it does no good. Is there something special I should do?

A. Too much fertilizer, especially nitrogen, will cause an abundance of vines and little fruit. They do not require heavy applications of fertilizer; in fact, many gardeners fertilize only once, just before planting.

Q. The bottoms of my beefmaster tomatoes split open when they start to turn red. What causes this?

A. Too much watering or rain when tomatoes are ripening causes the flesh to swell faster than the skin and the skin splits. Cut back on the watering.

Q. I have red raspberries which bear fruit in early summer and again in the fall. How should they be pruned?

A. The fruit is borne on shoots arising from lateral buds on 1-year-old canes. These shoots grow vigorously during the summer, initiate flower buds in the fall, overwinter and bear fruit the following season. The canes die shortly after harvest in late summer or early fall and should be removed in late fall. Cut back the new canes in late winter to a height of about five feet. Leave six or eight canes to a hill.

Q. At what stage of development should I pick black-eyed peas? Should they be green or should they be allowed to turn brown!

A. Harvest when they are well developed but before the pods start to dry out. The pods can be used the same as snap beans; the seed also can be used as dry beans.

Q. My Irish potatoes go to vine. How can I get them to bear potatoes?

A. Too much nitrogen fertilizer will cause a lot of vine growth and no potatoes. Too much shade also could result in no potatoes.

Q. We raised pumpkins this year for the kids for Halloween. How do I preserve them until the end of October when they will want to carve faces on them?

A. Pumpkins should be mature before being picked. Maturity can be checked by attempting to puncture the rind with your thumbnail. When the rind is firm enough so that it is hard to puncture, the pumpkin is close to maturity. After being picked, keep at a temperature of 80 to 85 degrees for about two weeks to cure. After curing, store in a dry place at 50 to 60 degrees. With good curing and storage, they should keep four to five months with little loss of quality.