Four very good books related to gardening have been published recently. Two are about garden insects, one is on flower arranging and the other on how to have an attractive garden with the least effort.

"Color Handbook of Garden Insects," by Anna Carr (Rodale Press, 256 printed pages, $12.95).

This is an all-color photographic handbook of virtually every orchard and vegetable garden insect. Egg, larval, pupal and adult stages are thoroughly described. With more than 300 color photographs, it is possible to identify most insects you would find in the garden. There is detailed information on their range, life cycle and feeding habits, and natural methods of control are suggested.

If you were to spend an afternoon sifting through the soil and examining the plants in one square yard of your garden, chances are you'd find well over 2,000 insects, the author says. Very few of these would pose any threat to the health and productivity of your plants. The fact is, most insects are directly beneficial to man and all are useful and necessary in the economy of nature.

More often than not we indiscriminately kill all the insects whether or not they are actually damaging the plants, she says. We forget that most of the insects present are actually helping us produce food and that some plant-eating species are necessary to complete the food chain. When we spray, pesky species are eliminated, and the insects, birds, and mammals that feed on them are also killed or leave the garden for greener pastures. The natural balance of predators, plant-eaters and pollinators is disrupted.

"The Art of Flower Arranging," by Martin Aaronson, published by Grower Books, London, and distributed here by ISBS, Inc., 2130 Pacific Ave., Forest Grove, Ore. 97116, 118 pages, well illustrated, $11.95.

The elements of design, texture, space, form and color are covered, also arrangements with accessories, those using wood, dried and preserved plant material and abstract arrangements.

Let flower arrangement be an art of natural and logical growth, with all that is good in the new adding to, rather than replacing, the time-tested old, says the author.

The life of cut flowers is a short one but there are one or two things that can be done to preserve it for as long as possible. When a stem is cut the cells start to close up. So the sooner the flower or leaf is in water, the better. Florists' flowers need recutting before being plunged into deep water for several hours, preferably overnight. If flowers are put in full sunlight or a very hot room, all the conditioning in the world will not do much to prolong their lives. Withering flowers can be revived by warm or hot water; the stronger the stem, the hotter the water can be, she says.

"Easy Gardens," by Donald Wyman and Curtis Prendergast and the Editors of Time-Life Books; retail distribution: Little, Brown & Co., 160 pages, beautifully illustrated, $8.95.

Low maintenance gardening does not mean letting nature grow rampant, the authors say. The trees and shrubs that form the bones of such a garden must be carefully chosen. Carefully plot your available space; it saves labor in the end, and the subsequent garden may not rival the grand gardens of Europe, but you'll have time to enjoy it.

We should limit ourselves to not more than a dozen varieties of plants, all of which would enjoy the type of sunlight, soil climate, space and care we would find time to give it. Keep lawns to a minimum or do away with them altogether. If you must have a lawn, install a mowing strip, which will keep you from having to trim edges near beds. And don't try to maintain grass on steeply sloped ground.

"What's Eating Your House Plants?" A guide to controlling indoor plant pests, by William H. Jordan, JR; Rodale Press, 229 pages, illustrated, $7.95 paperback.

Biological control of insects, says the author, doctor of entomology, University of California, takes attention, patience, knowledge and time. "It demands work. Don't even attempt to use it if you want a no-effort solution to insect control. It takes commitment. What you get in return are plants requiring few or no pesticide treatments. Toxic sprays and dusts have no place in the home. Learn to keep your plants healthy with natural controls."

There is a lot of interesting, very useful information in this book. It is well worth your while.