Choose the Right Varieties
Variety selections are also important when planning how to use the harvest in the kitchen. For canning and freezing, grow varieties that produce a concentrated harvest—such as determinate tomatoes, bush beans, pickling cucumbers, and broccoli varieties that form one large head per plant—and can then be pulled to make room for a new crop. For continuous harvests, choose varieties that yield consistently over a longer period, including pole beans, indeterminate tomatoes, and broccoli that produces sideshoots for weeks after the main head is harvested.
Climate, weather, and growing conditions affect variety choice and succession timing, too. Take bok choy and spinach. In spring, lengthening days and warming temperatures encourage these vegetables to bolt quickly. Sowing heat-tolerant varieties helps extend their harvest early in the year, but it is less important in fall, because the vegetables last longer in cooler weather. When buying seed or transplants, think about the potential challenges crops will face-high summer heat, humidity, cold springs, heavy soil, early fall frosts-and choose varieties that will perform best in your climate and the season you want to grow them in.
When planning successions and selecting vegetable varieties, consider how two or more crops might share the same space, a practice known as interplanting. Pairing plants with different maturity rates, like slow-growing Tuscan kale and lettuce, works particularly well because the lettuce heads mature before the kale grows big enough to shade or crowd them out.
Mixing plants with complimentary growth habits, such as lettuce, which has a deep taproot, and shallow-rooted scallions also makes efficient use of space and increases yields. So does planting short crops, such as beets and radishes, along the bottom of a trellis planted with peas, beans, or cucumbers.
Plant spacing also influences yield, and many crops can be planted closer together than most sources recommend. Tuscan kale seedlings are typically planted a foot apart, but spacing them at 10 inches encourages the development of small, long-bearing, tender-leaved plants. In good soil, a carrot needs only 4 square inches of space to grow in—so try sowing them 2 inches apart in a row, with 12 rows to a 30-inch-wide bed.
Some crops, including spinach and carrots, must always be seeded directly into the garden. Others, such as tomatoes and peppers, grow best when planted as seedlings. But many vegetables—including all greens, summer and winter squash, lettuces, and herbs like parsley and basil—grow well from seedlings or by seed. A simple way to get a staggered harvest of these crops is to sow seed and transplant seedlings into the garden at the same time. To keep each garden bed full and producing, try to have seedlings on hand and ready to go in whenever a space comes available.
Understanding how crops grow, learning to interplant and plan successions, and choosing varieties that thrive in specific conditions is the best way to overcome climate challenges. Gardeners in warm regions must take advantage of their tame winters by growing cabbages, greens, and peas, and appreciate their summers-and the melons, peppers, and eggplants that thrive in hot weather.
Mild summers give gardeners in cool climates the opportunity to grow a wider range of vegetables, including heat-tolerant varieties of cool-season crops and short-season varieties of heat-loving ones; and with the help of season-extension tools, they can grow greens and root crops into the winter, as well. Really, planning carefully and using a garden's space wisely makes it possible to grow more vegetables almost anywhere. It is, after all, a generous earth.