With the vegetable garden tucked away for winter and only onions and hardy greens soldiering on, it's the season to plan the next garden, your best yet. This is a perfect time to reflect on your past gardening successes and failures, to problem solve, and to dream of a lush and fruitful future.

Among other considerations for your garden plan, you might want to look at how plants relate to each other, supporting and encouraging their neighbors or competing with and even suppressing them. This can be a matter of choosing a plant that needs plenty of sunlight to pair with one that likes partial shade, such as tomatoes and lettuce, or avoiding plants that are known to inhibit each other, such as fennel and beans or tomatoes. By designing for mutually beneficial relationships, also known as companion planting, you can optimize the health and production of your garden.

Companion planting takes all aspects of a particular crop into consideration, from optimal soil condition to sunlight, relative size and spacing, length of growing season, need for support or protection, and chemical effects of one species on another. This knowledge, based on scientific testing, common sense, and your own experiences, is all a part of designing for a thriving garden community that promotes the best relationships among your plants.

For centuries, gardeners have planted beans, corn, and squash together in an arrangement known by Native Americans as “The Three Sisters.” The corn provides support for the beans which, in turn, provide nitrogen for the corn. Squash appreciates the shade from corn and beans and, in turn, suppresses weeds and helps deter animal invaders. This is the kind of win-win situation you'll want to plan in your garden.

Beans are one of the most popular vegetables and, fortunately, get along well with many other plants. They thrive with carrots and cabbage, and are also happy with beets. Beans and potatoes are traditional companions: Planted in alternating rows, beans discourage the Colorado potato beetle while potatoes repel the bean beetle. On the other hand, beans are inhibited by onions and garlic.

Plants such as dill and buckwheat can be sown here and there around the garden and are generally useful for attracting beneficial insects, but you should know that mature dill will suppress the carrot crop. You will either want to pull the dill before it goes to seed or not plant it near your carrots. Carrots and leeks can be sown together and because the carrots are harvested first, the leeks will have room to mature. Leeks, onions, and strong smelling herbs seem to repel the carrot fly.

Cabbage also benefits from aromatic herbs such as dill, sage, chamomile, and rosemary, which may repel the white cabbage butterfly. Additionally, sage is thought to improve the digestibility of cabbage. Tomatoes also have been known to keep the cabbage butterfly away. Broccoli is in the same family as cabbage and follows the same general rules for cultivation.

Tomatoes, parsley, and basil go together as well in the garden as they do on the table. Lettuce, carrots, and radishes is another group that works together as plants and as food. In fact, lettuce can be grown under tomatoes where it benefits from the shade in summer. Imagine your complete summer salad grown in one area with optimized growing conditions for the plants. And so convenient to harvest!

In smaller gardens, creating a mixed jumble of plants can work beautifully, as long as you don't combine those that really don't get along. Among the advantages of mixing up your plantings are being able to grow more in a smaller space, deterring insect pests by confusing them, and attracting beneficial insects. It imitates nature by creating a biologically diverse environment that promotes healthy plants and soil. With flowers in the mix, it can be quite beautiful.

For larger gardens, you may want to keep plants in rows for easier management. Try alternating crops or pair them with their preferred companions in wide rows. A row of radishes and lettuce planted right alongside peas is mutually beneficial, or plant potatoes and peas together. The potatoes will appreciate the nitrogen from the pea roots. Fill any spaces in the rows with flowers to keep the ground covered while attracting beneficial insects.

Sunflowers, with their sturdy stems, can provide a wind break, shade, and support for cucumbers and other vines, and at the same time, they attract beneficial insects and birds. However, sunflowers and potatoes are known to stunt each other, which is a reminder to be aware of both the “good company” and the less productive relationships.

You'll want to tuck in a marigold wherever there's an available spot in your garden as a deterrent to nematodes. Because pests will look for their host plant and then gobble their way right down a row, it's smart to confuse them by interplanting with something they don't like. Flowers are a good choice for this, tucked in here and there and especially around the perimeter of the garden. Cosmos, calendulas, and yarrow will interrupt the path of a pest and attract beneficial insects, as well as adding lovely color to the garden. Nasturtiums not only deter aphids but act as an attractive ground cover, not to mention both the leaves and flowers can be added to your salad.

Radishes are a good friend to most other vegetables in the garden. Many gardeners use the quick-germinating seeds to mark the planting of other crops. Grown together with nasturtiums and vine crops such as cucumbers, they help to repel beetles and borers and are, in turn, protected from flea beetles.

Flea beetles seem especially fond of eggplants, so you will want to plant plenty of aromatic herbs around them. Also, try to keep the ground shaded by spacing plants as close as is reasonable. This will help deter the flea beetles as well as keep weeds down.

Along with eggplants, peppers belong to the tomato family. They can all be planted in the same neighborhood and respond well to similar cultivation. Again, mixing them all together with some salad greens, basil, and flowers might just be the best way to confuse and deter their pests. Potatoes are also in that family, but apparently give off root excretions that inhibit the growth of tomatoes, so they should not be planted near each other.

There is a lot of information about companion planting, some of it scientifically based and some anecdotal. Particularly useful books are, Great Garden Companions by Sally Jean Cunningham and Companion Plants by Helen Philbrick and Richard Gregg.

Since every garden will reflect the individual planning and planting styles of the gardener, and there is so much variation in terrain, the design possibilities are limitless. Along with the key ingredients of fertile soil, sunlight, water, and choosing appropriate plants, planning for “good company” in your garden will reward you with your own version of a thriving plant community.