The fact that spring is less than a month away weights heavily on the minds of back yard gardeners about this time of year. not only are they concerned with getting the soil ready and slecting seed varieties that grow well here, but also with tailoring the garden to meet their personal style.

No longer are the choices cut and dried. More than ever before, gardeners are thinking well beyond funny-shaped carrots and curly leafed parsley. Some are even specializing and devoting their entire gardens to herbs, salads, nutrition, high yields or nouvelle cuisine. Tomatoes may still be essential, but baby vegetables have taken root alongside them. But, whatever the concept, the time to start planning is now. Getting Started

"The key is thinking precisely about what you want and then planning for it," said Jack Ruttle, planning editor at Organic Gardening magazine. One way to start is by reading through the listing of herbs, fruits and vegetables found in the front of seed catalogues or in gardening books and making a list of what you'd like to grow.

Concentrate on things that everybody likes, Ruttle said. Particularly when selecting high-yield crops such as zucchini, tomatoes and beans, think to yourself, "Does everybody like this?" he said. Then get a calendar with plenty of writing room under the dates and write in the actual planting times. Doing all your planning for the same day of the week is better than haphazard picking and choosing, Ruttle said. This way you always know that on a particular day you have some gardening work to do. "I like Sundays, so almost every Sunday, starting in mid-April, I write in actual planting times. I seed lettuce on Sunday, for example, and transplant it on a Sunday three weeks later," he said.

It is also important not to select and plant more produce than you think your family will use, said Ruttle. Just as it is a bad idea to grocery shop when you are hungry, sort through seed catalogues after a filling Sunday brunch or dinner.

"The biggest problem people have is planting too much and all at once," he said about the pitfalls of gardening. "It's false economy." Overplanting leads to a crop glut, he said. "You get a whole row of cabbage and the lettuce goes to seed because you can't use it all. Four well-cared-for tomato plants will give you all you can eat, some to give away and some to can or freeze," he said. It's also important to plant early and late varieties of the same crops, so you have an overlap of the same kinds of foods with different maturing times.

In addition, you don't need an acre of land to plant all you'll need. In fact, many experts say that the smaller your garden space, the more efficient it will be. A 20-by-20 foot garden, for example, should produce enough fruit and vegetables to feed a family of four, said Tricia Gabany, director of Garden Resources of Washington (GROW).

It should take about 25 hours to prepare the bed, which includes breaking the ground, adding leaves and fertilizer, having your soil tested at the nearest cooperative extension service for nutrients and acidity, and planting the seeds, Gabany said. Since soil in this area tends to be heavy in clay, shredded leaves and manure (free from the Rock Creek Stables) must be worked in to break it up. Compost, if you have it, is also helpful. Ideally this should have been done in the fall; however, it's never too late. Just be sure to work the soil only when the ground is thawed and dry, she said. If a handful of dirt holds together in a ball then the ground is too wet.

Choose a level, convenient spot, with no standing water (good drainage is essential). There should be six to eight hours of continual sunlight, Gabany said. In addition, depending on how much the garden has been mulched, the gardener should plan to spend about three hours a week weeding, watering and mulching. It's best not only for the gardener, but also for the produce if gardening is done early in the morning, Gabany said. Produce picked at the end of the day is very warm, and won't hold as long as that which has had time to cool off during the night, she said.

Bear in mind that there are three growing seasons in Washington. You should be planning spring, summer and fall gardens, said Nancy Flinn, director of public relations at Gardens for All, a national support group in Burlington, Vt., for back yard and community garden groups. Seasoned gardeners call this succession planting.

Hearty vegetables such as broccoli, cabbage, celery, leafy greens, garlic, onions, peas, radishes and turnips can be planted between March 15 and April 15 in the District, and 15 days later in suburban areas, according to the Cooperative Extension Service of Maryland. After April 10, the last likely date for successive nighttime frosts, semi-hardy vegetables such as beets, carrots, cauliflower, endive, lettuce, parsnips, white potatoes and herbs can be planted. All of these plants can be replanted in late August for a fall crop. With any luck at all, you should be harvesting lettuce right up to Thanksgiving, Flinn said.

Around the middle of May, after all danger of frost has passed, it is time to plant the "tender" crops. Included in this category are sweet corn, snap beans, cucumbers, squash, cantaloupe, eggplant, peppers, sweet potatoes, okra and tomatoes.

Marigolds, radishes, turnips beets, carrots, endive, lettuce, parsnips, white and sweet potatoes, sweet corn, snap beans, cucumbers, squash, cantaloupe and okra can be started directly in the ground, said GROW's Gabany. All others must be started indoors. You'll want to get at least two sets of leaves on the vegetables before you transplant them, Gabany said. Generally it is 4-5 weeks before hearty and semi-hearty vegetable seeds can be transplanted, and 6 to 8 weeks before the tender vegetables can be transplanted. In addition, plants need to "harden off" for a week before being put in the ground. Put them outside during the day and bring them inside at night.

"You have to be committed to your garden over the long haul," said Gabany. If you want to plan a summer vacation, you must make sure someone will come around to take care of the garden while you are gone, she said. In addition, mid-summer gets hot and the garden can quickly go to weed if you don't have time to clean it out. Any gardener will lose his enthusiasm on a 90-degree July afternoon when looking at a garden full of weeds to pull and several pounds of zucchini to pick, even though he is full to his ears of zucchini bread.

Finally, don't be discouraged by any failures your first garden may have, Gabany urged. "It takes a year to know what you are doing." Write down what does and doesn't work this year and use it for planning next year's garden. "A lot of a garden is personal style," she said, "and how much time you can devote to it." With any luck at all, by this time next year, you'll be weeding out those vegetables you didn't use and replacing them with exciting new ones.

Besides getting your garden plot in shape, you must plan how to fill it in. You may want an all-purpose kitchen garden, or prefer to concentrate on just a single segment -- an herb garden, a salad garden, or one geared for cooks into nouvelle cuisine. All-Purpose Kitchen Garden

If you limit your selections to the area's most successful all-purpose crops, you'll still have plenty to eat and a good deal of variety, said GROW's Gabany. Among the most popular are tomatoes, bush and pole beans, chinese cabbage (bok choy), brassicas (cauliflower and broccoli), kohlrabi, onions, carrots, butternut squash, zucchini, hot and sweet peppers, purple eggplant, sweet potatoes, corn, radishes, leafy greens such as kale, spinach and lettuce, peas and all herbs.

Some varieties grow better than others, however, Gabany said. Tomato plants are particularly susceptible to verticillium wilt, so select those varieties with a "VF" in front of the name, she said. Green Crop bush beans and Kentucky Wonder pole beans produce the area's highest yield. Since lettuce tends to bolt during our humid summer days, you'll want varieties that are resistant to the problem. Tom Thumb lettuce, a cross between head and leaf lettuce, is a good choice for green lettuce. For color, try the new red-leaf lettuce variety called Red Sails. There are more than 20 varieties of radishes to choose from, ranging in color (white, yellow, red) and shape (elongated and round). Choose the round red varieties for problem free crops, Gabany said. Sweet potatoes and corn both grow well in Washington, but they also need plenty of space. For a good variety of herbs plant basil, thyme, parsley, mint, dill and chives.

It's also nice to plant a border crop of marigolds, Gabany said. Not only are they attractive around the garden, but they are edible and look pretty sprinkled on salads. However, there's no substantiation to the rumor that marigolds rid the garden of pests, Gabany said. "Still, I love the look." The Herb Garden

"Selecting which herbs to grow is a little like walking into a candy store and saying, 'I want red candy,' " said Tom DiBaggio, owner of Earthworks Nursery in Arlington and editor of Gerard's Garden. "There are all kinds of flavors." No one knows just how many herbs there are in the world, he said, adding that there are more than 25 bonafide varieties of mint, 400 varieties of thyme and 750 varieties of sage.

For this reason it is important to be selective about the herbs you choose to grow, he said. "There's nothing worse than an herb garden that goes unused. Herbs grow better the more they are used." If you don't know what you want to grow, he advises going into a nursery and smelling the different leaves.

Of all the specialty gardens, an herb garden takes up the least space, DiBaggio said. They are good for growing in containers. "In colonial times that's exactly how they were grown," he said. But they are difficult to grow from seed because the seeds are so tiny. If you put them in the ground too soon, before the frost has ended, the growth is checked, he said. So it's best to start them inside, four inches from a growing light.

Complicating your herb choices is the fact that some herbs return year after year and others do not. There are three categories for growing, DiBaggio said. In the perennial category (plants that continue to live after they flower) are chives, lovage, mints, oregano, sage, winter savory, french tarragon, thyme and sorrel.

Some of the common annuals (plants that flower and die) are basil, chervil, dill, parsley, summer savory and cilantro (chinese parsley). And in the tender perennial category (plants that will flower and continue to live provided they are brought inside or protected from the winter with a cold frame) are chervil, parsley, sweet marjoram and rosemary. It is best to plant the perennials away from the other herbs so you can work that part of your garden where nothing is growing in the fall, DiBaggio said.

As for using those herbs, "The Herb Garden" by Sarah Garland (Viking, $27.50, hardcover, $12.95 paperback), offers the following culinary guide:

Stews and soups: bay, coriander seeds, juniper berries, lovage seeds and leaves, parsley stems, rosemary, savories, thyme.

Egg dishes, summer soups: basil, chervil, chives, dill, fennel, sweet marjoram, mint, parsley, sorrel, tarragon, lemon thyme.

Poultry: Fennel, sweet marjoram, tarragon, summer savory.

Tomato dishes: basil, marjoram, mint, summer and winter savories, tarragon.

Curries: Aniseed, bay, coriander seed, cumin seed, fennel seed, fenugreek seed, mint, mustard seed.

Fish: Caraway, dill, fennel, lemon thyme and parsley.

Roasting meats: Bay, fennel stems, rosemary, savories, thyme.

Marinades: Bay, coriander seed and leaves, cumin seed, dill, juniper berries, parsley stems.

Bouquet garni: Bay, marjoram, parsley stems, thyme. The Salad Garden

The ideal salad garden should have a wide selection of herbs, vegetables and edible flowers. Not only will the yard be beautiful, but the yield will make a spectacular presentation at the table.

The advantage of salad gardens is that they "tend to be very intense," said Joy Larkcom, author of "The Salad Garden," (Viking, $27.50 hard cover, $12.95 paperback). "You can get an awful lot in a square yard."

So, if your salad garden space is particularly small, she advises that back yard gardeners think in terms of planting "ceiling" crops -- those that can be trimmed to 2-3 inches high and continue to grow. Included in this category of greens are lettuces, rocket (arugula), sugar loaf, cresses, rape, chicory and spinach. These plants also fit into the category of high-yield crops, in that they are very bulky and you get a lot from one plant. Other high-yield crops are herbs, chinese cabbage, tomatoes and belgian endive.

Still, her salad garden takes up almost half an acre in her yard in Suffolk, England, and at any time of the year there are 10 to 20 herbs and vegetables ready to use in salads, she said. Winter is the scarcest time of year, when the vegetables grow in a polyethylene tunnel.

"Lettuce is almost a minor crop," she said, "because they take a long time to mature. Still there is tremendous variety in color and texture, from the soft butterhead to the red-leaf varieties, to consider in your own garden, she said. You should also consider the wide range of radishes in all colors and shapes (elongated, round and red, yellow and white). Even though in the Washington area some of these varieties take more care than others, it is worth the effort. You should also include red cabbage, kale, celery and fennel.

Flowers are easily grown and should be in any serious salad garden, she said. A good selection would be sweet flavored borage, peppery nasturtium and daisies for their beautiful petals. Pick them in the morning when the dew has rinsed them off, as flowers don't wash easily and the petals tend to stick together. When using them in salads, add them after the dressing has been tossed in. "Oil spoils their look and tossing them bruises the petals, she said.

You can use almost any herb on a salad. The amount you use depends on the strength of its flavor. Peppery chervil is her favorite salad herb, but she doesn't limit the garden to just one. "I use them in combination, and collect what hits my eye."

Remember to grow those herbs that your family will like, and when they need thinning, simply cut them back and freeze, dry or store them in olive oil. Other unusual salad herbs include anise, parsley, caraway, chervil, dill, coriander, basil, thyme, chives and rosemary. The Nouvelle Garden

Think beautiful and miniature when you think how your nouvelle garden should grow. In fact, think bite-sized; and think color. Inch-long courgettes (baby zucchini) and yellow squash (both with their flowers left in place, filled with mousse or left alone) are gorgeous on the plate. Carrots so young that their skins haven't had time to thicken require only a thorough scrubbing, then steaming, and can be served with another inch of green left at the tops. Think of red and yellow plum miniature tomatoes (not the cherry variety) and serve them with tiny bundles of red and dark green lettuce, as Nora Pouillon does in her Dupont Circle Restaurant Nora.

Plant your corn and pick it young. The flavor is intensified. The corn tastes wonderful raw, and when it is lightly steamed the flavor is so sweet that butter seems to hide rather than enhance the flavor.

Plant thin french green beans, red and green swiss chard, mustard greens and rape. Use the greens in tiny quickly steamed timbales or in freshly made soups. Jason Wolin hardly does anything to his greens, using them as simple stir-fries and then splashing them with a little oil at his Washington restaurants, 209 1/2 and Mrs. Simpson's.

Roast your yellow, red and green peppers, then use them to garnish fish, or to make colorful sauces and chili butters, or cut them in little pieces for spinach salads. Alternate the colors on a large platter and marinate them with oil and herbs for several hours and serve them as a first course. Use mache (lambs ears or lambs quarters), radicchio, endive, arugula in your other salads or to surround and line platters.

Use flowers for garnishment and flavor, Pouillon said. Her favorites: lilies, for their beauty; nasturtium, for their peppery flavor and tiny purple chive flowers, that are so full of flavor that if you eat just one you feel you ate a whole onion, she said.

Basil, oregano, tarragon, sage, chervil, lemon thyme, english thyme, flat parsley, lovage, winter savory, borage, pineapple mint, spearmint and peppermint, saffron (nothing more than the filament of a saffron crocus) are some of the herbs to think about. Use them not only to flavor, but in whole sprigs as garnishment.

Use all of these in various combination. Cook them lightly, only to remove their hard edge, and serve them overflowing your prettiest bowls.