More in Outdoors
Many root crops appreciate well-drained, slightly acidic soil that still holds organic matter and some of the nutrients dug in for a previous crop. However, potatoes crop best on recently manured soil, and brassica root crops (radishes, rutabagas, and turnips) may succumb to clubroot in acidic soils that have not been limed. Stony soils may cause malformation of long-rooted crops.
Most root crops are grown from seed, sown from early spring into outdoor seedbeds. Sow seed into drills at the appropriate depth, cover with soil, and water in. Sow carrots, beets, turnips and radishes successionally every few weeks for a continuous supply. Seed potatoes are actually tubers, which should be left to sprout (chit) in a cool, light place before planting into a deep drill or individual holes.
Thin seedlings out, leaving strong plants to grow on at the correct spacing. Keep the surrounding soil weed-free and moist, watering as necessary in dry spells. Protect potato plants from frost and cover their lower stems and leaves with soil (earth up) as they grow. Potatoes often suffer from blight in damp weather. Carrots, parsnips, and brassicas are also prone to certain pests and diseases. Employ measures to minimize the risk of attack and also try growing resistant varieties.
Most roots can be left in the ground until needed, although they should be protected from frost. Lift potatoes by early fall, allow them to dry for a few hours, and store in paper sacks in a cool dark place.
Protecting against carrot flies A 24-inch barrier of very fine netting, fleece, or plastic, stretched around secure posts and buried at the base, is sufficient to keep carrot flies at bay (image below). The females fly close to the ground and are unable to reach the carrots to lay their eggs.
Roots in pots Carrots, beets, and radishes all grow happily in containers at least 10 inches wide and deep (potatoes need larger pots), as long as they are kept well watered. This is a good way to start the earliest crops under cover.
Growing potatoes through black plastic If earthing up potatoes sounds like too much effort, try planting your crop through holes cut in a layer of thick black plastic—push the edges into the soil to secure the plastic in place. This keeps out the light and helps warm the soil for a fast-maturing crop.
Potato (image 1)
Early varieties suit small gardens since they are harvested by midsummer, whereas maincrops tie up the soil until mid-fall.
Beet (image 2)
Not all beets are red, so you can choose unusually colored varieties and opt for bolt-resistant types for early sowings.
Parsnip (image 3)
These roots will stand in the soil through winter with a covering of straw, but seeds need to be sown the previous spring.
Radish (image 4)
Sow radishes successionally for crops over a long season. Exotic hardy winter radishes can also be sown in summer.
Excerpted from Simple Steps: Vegetable Gardening
© Dorling Kindersley Limited 2007