Miraculously, each October grocery shelves are filled with red and yellow and green glaceed fruits, hazelnuts, whole Brazil nuts, almonds in pound packages. Have you ever tried to buy hazelnuts in August? Where have they been since last December?

From December to October these ingredients are more difficult to find than a small child when a mother wants the dishes dried.

If you plan to bake fruit cakes for Christmas 1979, it's that time of year again. Especially if you want to age them.

Baking Christmas sweets is a tradition engaged in by many people who do not fit the picture of the "traditional" homemake, whatever that is these days. I know some people who ordinarily use their kitchens only for making coffee, but insist on recreating the family's old fruit cake recipe each fall. They feel they are the keepers of a holiday ritual without which Christmas just wouldn't be Christmas.

On the whole I'd rather have a homebaked fruit cake that contains $10 worth of ingredients than a picnic hamper filled with $100 worth of canned delicacies. The contents of the hamper just won't create the same feeling.

In addition to acting as keepers of the tradition, people bake their own fruit cakes for other reasons: Because they want more (or less) cake than fruit; because they want to give a homemade gift.

Somehow, the baking of fruit cakes appears to strike terror in the uninitiated. Actually, it is among the easiest cake to make. There is no complicated folding, shaping or rolling; just a mixing of the ingredients. And the texture of a cake laden with fruits and nuts is not as important as it would be in a layer of sponge cake, so it's difficult to either over or under beat them.

The only tricky part is the fruit cake's tendency to burn, so it must be watched carefully. If the top browns too rapidly it can be covered lightly with alumimum foil.

On the other hand, a fruit cake must not be overbaked. A cake tester inserted in the center must come out free of unbaked batter, but it should be moist and sticky.

Fruit cakes are best if soaked with spirts -- brandy, bourbon, rum, sherry or other sweet wines. But if you do not wish to use alcoholic beverages, orange juice or apple cider can be substituted.

And if you don't care for the choice of fruits and nuts in the recipe, you can change them, too.

If you think it's time to start your own tradition, these fruit cake recipes should provide something for every taste: one has more cake than fruit; another has mostly dried fruits with just a smattering of the glaceed fruits; one has lots of bourbon; another is unbaked. SYLVIA'S FRUIT CAKE

This cake is especially for those who don't care for too many candied fruits. Do not chop the nuts or cut up the fruit. (Makes 1 large 6-pound cake) 1can (8 ounces) walnuts (2 cups) 1 can (8 ounces) pecans (2 cups) 1/2 pound shelled Brazil nuts (1 1/2 cups) 2 packages (8 ounces each) pitted dates 1 box (15 ounces) dried apricots 12 pitted prunes, halved 4 ounces mixed candied fruits 1/4 cup raisins 1 1/2 jars (8 ounces each) maraschino cherries, drained (1 cup) 1 1/2 cups sifted unbleached flour 1 teaspoon baking powder 1 teaspoon salt 6 eggs 1 cup sugar 2 teaspoons vanilla 3/4 cup brandy

Grease the bottom and side of an 8-cup souffle dish or a 9-by-5-by-3-inch loaf pan. Line with brown paper; grease paper.Combine walnuts, pecans, brazil nuts, dates, apricots, prunes, candied fruits, raisins and cherries in large bowl. Sift flour, baking power and salt over nuts and fruits. Toss lightly until well coated.

Beat eggs, sugar and vanilla in a medium-size bowl with electric mixer until fluffy and light. Pour over nut mixture. Stir gently to combine.

Fill prepared dish or pan, pressing cake mixture firmly so it will hold its shape after baking.

Bake at 300 degrees for 1 hour and 45 minutes. (If fruits are browning too quickly, cover with buttered foil) Remove cake to wire rack. Spoon 1/4 cup of the brandy over cake. Let stand 1 hour. Invert; peel off paper; turn right side up; let stand on wire rack in shallow pan; spoon remaining 1/2 cup brandy over cake.

To store: Wrap in cheesecloth that has been soaked in brandy. Wrap in heavy-duty foil or store in a tightly covered container. Martha Washington's Great Cake (makes 2 loaf cakes) 1 1/2 cups golden raisins 1cup currants 1 cup water 4 ounces candied orange peel 4 ounces candied lemon peel 4 ounces candied citron 3 1/2 ounces candied red or green cherries or combination 1/4 cup brandy 5 eggs, separted 1 cup sugar 1 cup (2 sticks) butter, softened 1 teaspoon lemon juice 2 1/4 cups sifted unbleached flour 1/2 teaspoon ground mace 1/4 teaspoon ground nutmeg 2 tablespoons sherry Sherry or brandy Candied cherries

Soak raisins and currants in water in small bowl overnight. Combine orange peel, lemon peel, citron and cherries in medium-size bowl; sprinkle with brandy; let stand overnight.

Grease two 8 1/2-by-4 1/2-by-2 1/2 inch pans. Beat egg whites in medium-size bowl with electric mixer until foamy-white. Beat in 1/4 cup of sugar slowly until merringue forms stiff peaks; reserve.

Beat the butter, remaining sugar, egg yolks and lemon juice in large bowl with electric mixer at high speed until light and fluffy (about 5 minutes).

Sift flour, mace and nutmeg onto wax paper. Stir into batter alternately with sherry, blending well.

Drain raisins and currants.Add to batter with candied fruits and brandy, mixing well.Fold in reserved meringue until no streaks of white remain. Pour batter into pans. Place a roasting pan on lowest rack of oven. Fill halfway with boiling water. Place cakes on middle rack of oven.

Bake at 350 degrees for 20 minutes. Lower heat 325 degrees and bake 55 minutes longer or until centers spring back when lightly touched with fingertip. Cool cakes in pans on wire racks 15 minutes. Remove from pans; cool completely.

To store, wrap in sherry or brandy soaked cheesecloth; place in tightly covered container for a month or longer. Pour more sherry or brandy over cake when cheesecloth dries out.

Garnish with candied cherries,if you wish. WHISKEY CAKE (makes one 10-inch tube cake) 3 eggs, separated 3/4 cup granulated sugar 1/2 cup (1 stick) butter 1/2 cup firmly packed dark brown sugar 1 1/2 cups sifted unbleached flour 1 can (8 ounce) pecans, chopped (2 cups) 1 cup seedless raisins 1 teaspoon baking powder 2 teaspoons ground nutmeg Dash salt 1/2 cup bourbon Peacan halves for decoration Candied cherries (optional)

Grease and flour a 10-by-4-inch tube pan.

Beat egg whites in small bowl with electric mixer until foamy-white. Beat in 1/4 cup of the granulated sugar slowly until meringue forms stiff peaks; reserve.

Beat butter, brown sugar, remaining granulated sugar and egg yolk in large bowl with electric mixer until light and fluffy.

Mix 1/4 cup of the flour with pecans and raisins in small bowl, stirring until nuts and fruit are coated.

Sift remaining 1 1/4 cups flour with baking powder, nutmeg and salt onto wax paper. Add bourbon until well blended. Stir in pecans and raisins. Fold in reserved meringue until no streaks of white remain.

Spoon batter into prepared pan, pressing down with spoon to pack pan. Decorate top with pecan halves.

Bake at 325 degrees for 1 hour, or until top springs back when lightly pressed with fingertip. Cool in pan on wire rack for 1 hour. Remove from pan; cool completely. Wrap cake with cheesecloth soaked with bourbon. Store in tightly covered container several days. Decorate with cherries, if you wish. NO-BAKE FRUIT CAKE (makes 4 small loaves) 5 cups crushed graham crackers 1 cup pitted prunes 1 cup dried apricots 1 cup pitted, sliced dates 1 cup raisins 1/4 cup dark rum 1/4 pound butter 1/2 cup confectioners' sugar 1/2 cup orange marmalade 1/2 teaspoon salt 1 teaspoon cinnamon 1/2 teaspoon ground cloves 1/2 cup chopped walnuts

Crush in graham crackers between two sheets of wax paper with a rolling pin, or in the blender, or in a food processor. Coarsely cut the apricots and prunes and combine with dates and raisins. Pour rum over the fruits.

Beat the butter with the sugar, marmalade, salt, cinnamon and cloves until thoroughly blended. Mix with nuts, fruits and crumbs. Mix until well blended.

Oil eight 2-by-4-inch loaf pans or one 8-by-4-by-3-inch pan and pack mixture in firmly, making sure there are no holes. Level off top. Cover and chill in refrigerator for two days or longer before serving in small slices.