Harvesting root vegetables is like digging up buried treasure. Out of the dark earth come brightly colored carrots, dusky beets and pale turnips delicately shaded with purple. These versatile vegetables can be enjoyed steamed, roasted, mashed and stir-fried as well as raw. All are nutritionally rich in vitamins, antioxidants and fiber. Carrots are an abundant source of Vitamin A, while sweet beets are a good source of Vitamin C. And beets and turnips offer the bonus of healthful, delicious greens in addition to their edible roots.
While they are not closely related botanically, carrots, beets and turnips share similarities in in how they grow and their cultural needs in the garden. All of these crops need loose, fertile soil and a regular supply of soil moisture in order to grow rapidly and form the tender roots we enjoy.
Roots crops are great candidates for growing in raised beds, as the extra soil depth gives the roots room to develop. Carrots and beets are suitable choices for small space gardens, with even a small patch producing a good yield. All are good keepers, given proper storage conditions.
The secret to success with carrots is deep, loose soil. Sandy loam free of stones and clods of soil is ideal. But don't despair if you garden in heavy clay or compacted or rocky soil; choose midget varieties that don't need to push their way deep into the ground.Work a few inches of organic matter into the soil before planting, but go easy on fresh manure and nitrogen-containing fertilizers. High levels of nitrogen cause carrots to develop lots of fine feeder roots, making them unappealingly "hairy." The ideal soil pH is around 6.5.
Sow seeds directly in the garden, beginning about 3 to 4 weeks before the last expected spring frost, making succession plantings at 2 to3 week intervals until the weather heats up in midsummer. Gardeners in warm climates can sow seeds in the fall for harvest in the spring.
Carrot seeds are very small, which makes it difficult to sow them thinly. Mixing carrot seeds with sand makes spacing a little easier. Carrot seeds can be slow to germinate and the tiny seedlings sometimes have trouble breaking through crusted soil. Sprinkling vermiculite or sifted compost over the seeds instead of covering them with garden soil helps, or you can mix radish seeds in with your carrots. The radishes germinate quickly, breaking up the soil crust as they emerge and making it easier for the later emerging carrots to push through. And harvesting the radishes automatically thins your carrots!
Once carrot seedling are up, be sure to thin plants to the recommended spacing, keep soil moisture consistent and keep weeds at bay. As roots begin to size up, pull up some test roots to sample. When they are sweet and fully colored, it's time to harvest.
Beets need much the same soil preparation as carrots and, like them, grow best in the cooler temperatures of spring and fall. One thing to keep in mind about beets is that the "seeds" you plant are really dried fruit capsules containing multiple seeds. So no matter how widely you space them, you are always going to need to do some thinning. When you see the first set of true leaves forming on seedlings, use a pair of scissors to snip out all but the strongest in each clump. Don't pull out extras at this stage or you'll harm the fragile roots of your "keepers." A few weeks later, make a second thinning, spacing plants about4-6 inches apart. The tender thinnings are great in a salad.
Like carrots, beets need consistent moisture to produce sweet, tender beets. An organic mulch will help to preserve soil moisture. In many areas, young beet plants are prime targets for leaf miners and flea beetles. Cover the seedbed as soon as you plant with a floating row cover to exclude these pests.
Both these cool weather crops are members of the mustard family. Turnips produce mild-flavored, round roots in a variety of colors. More strongly flavored rutabagas, also called Swedish turnips or swedes, form roots about 5 to 6 inches in diameter that store well.
Like other root crops, they do best in deep, loose, well-drained soil amended with organic matter. Plant turnips in the spring as soon as the soil can be worked, making succession plantings until hot weather arrives. Start a fall crop 8 weeks before the expected fall frost date. Gardeners in warm areas can continue to plant every few weeks through the winter.
Rutabagas, especially if grown for storage, are best planted in early summer in northern gardens and mid to late summer in southern areas, about 12 weeks before the fall frost date. Rutabagas that mature when the weather is cool will have the sweetest, mildest flavor.
Q: The tops of my carrots always turn green and bitter-tasting. How can I prevent this?
A: The top of a carrot root turns green when it is exposed to sunlight, which happens when the carrot shoulders its way out of the soil as it grows. To prevent this, simply hoe some soil up over the the tops of the roots periodically to keep them in darkness.