Beautiful arrangements of dried flowers are used as centerpieces at Mount Vernon, Colonial Williamsburg and Monticello during the winter. Gardeners can make the same arrangements. It's fairly easy, and there are several methods.

The oldest and easiest is to take the flowers when they first open and hang them upside down in small bunches to dry. Everlasting and strawflower are old favorites. Others that dry easily are astilbe, babysbreath, cockscomb, globe amaranth, golden rod and yarrow. Now is a good time when they are plentiful.

The best method for most flowers is to bury them in silica gel or mixture of borax and corn meal. This will perserve the color better than air drying.

Some of the best flowers are drying in silica gel or borax are calendula, cosmos, dianthus, foxglove, gillardia, glorisa daisy, larkspur, lupine, marigold and zinnia. The small-flowered dahlias, chrysanthemums, sunflowers and opening rose buds also may be used.

About a week is required in silica gel and two weeks in borax and corn meal. Silica gel can be purchased from your florist or at most large garden centers. It can be used over and over again. When the blue crystals become pink after use, it may be dried in an oven at about 250 degrees F. until the blue color returns.

Use one part borax to three parts corn meal; this mixture can also be dried for repeated use.

Flowers to be preserved for drying should be picked when they are free of moisture. Open buds may be used, or flowers in any stage of development before full bloom.

The true yellow, orange, pink and blue colors are best. Red and purple colors become darker and less attractive. White flowers usually become buff or tan in a short time.

Opening buds or small flowers with short stems may be completely buried in the drying material in a closed metal or plastic container. Shake the container gently as the silica gel or borax is added to be sure it comes in contact with all parts of the flower.

A carton of medium depth or a shallow box may be used for flowers of medium and large size. Place about one inch of the drying material in the bottom of the container. Stand single-head type flowers, like daisies, head down in the mixture. Be sure the petals from a smooth circle. Carefully add silica or borax until the flowers are completely covered. Spike-type flowers like larkspur and snapdragon may be laid on their side in a shallow box. Q: I live in a garden apartment and have planted shasta daisies and mums in pots on my terrace. I have been told that if I leave these plants outside all winter, they will be killed. What's the best way to protect these plants over the winter? A: Being above ground, the temperature of the soil around the roots in the pots will be about the same as the air temperature. If the temperature goes below freezing, the roots will be killed. The best thing that can be done is to store them in garage or basement where the temperature will range between 35 and 45 degrees. Q: How old must a pine tree be before it starts to bear cones? A: The digger pine of California and jack pine of the Lake states may bear cones as early as the third year; the lodgepole and pitch pine at five to six years; eastern white pine, longleaf and shortleaf pines rarely bear cones until after 10 years; the sugar pines of the west seldom bear cones before they are 40 to 50 years old. Q: I have two minature roses that were given to me; they are growing outdoors in pots. What shall I do with them during the winter? A: They will not survive the winter outdoors in pots. Bring them inside and grow them on a sunny windowsill or under fluorescent lights. If given good light and good care they should bloom all winter. Q: The past two years our peaches from our drawf tree were wonderful, but this year they have all been moldy. What happened? A: It probably was a fungus disease called Brown Rot. Spraying with an all-purpose fruit-tree spray usually provides fairly good control of the disease. It can be purchased at large garden centers or farmers supply stores. Directions on the label should be followed closely. Q: I have yew 16 feet tall that had about 40 red berries last year and several hundred this year. There is no male plant nearby to provide pollen for it. Isn't this very unusual? A: There is a record of femal yews sometimes bearing a few male (staminate) flowers, and of male plants sometimes having a few female (pistillate) flowers. To be able to count on pollination for the female, a male plant should be planted in the immediate vicinity. Q: This year I had lots of little squashes but before they even half matured they were all dying, vines and all. What could have done it? A: The squash -- also cucumber, cantaloupe, pumpkin and watermelon -- are subject ot attack by squash vine borers. The mature stage is a day-flying moth that overwinters in the soil. The moth lays eggs on the stems near the ground, the tiny caterpillars bore into the stems, the plant wilts and dies.Specialists recommend spraying or dusting the lower part of the stems with Sevin at weekly intervals three or four times, starting when the first flowers start to develop. Directions on the label should be followed closely. Q: I want to store a load of fireplace wood in my basement but I don't want to bring termites into my house. Would it be safe to bring the wood indoors after a slight freeze outside? A: The subterranean termite is the one that does the damage, and it cannot survive freezing temperatures. It's a good idea to wait until after a hard freeze to be on the safe side. Q: My sister and I each planted a paper birch tree in our front yards three years ago. Her tree was killed by borers this year. Is there anything I can do, other than spraying, to protect my tree? A: Try to keep it in the best of health, prune out all dead and dying wood, fertilize the tree in the late fall after it becomes dormant, and water it regularly and thoroughly during dry summer weather. Q: I have seeds from a Grimes Golden apple and I'd like to plant them to get an apple tree. How should I go about it? A: The seeds do not come true and the tree you get may be practically worthless from the point of view of producing quality fruit. The seeds can be planted outdoors immediately after they are removed from the apple. Plant them 1/4" deep, mulch them, and in the early spring remove the mulch.