Choose and prepare the site as you would for spring radishes, but till the soil deeper, to at least a foot. Plant seeds in spring or winter, depending on the variety. Thin plants to six inches, and mulch to suppress weeds and retain moisture. They can't survive frigid weather, though, so harvest all your plants before the first hard freeze. Winter, or long-season, radishes are larger, take two months or more to reach maturity, and store better than their spring counterparts.
Radishes are great companion plants.
They draw aphids and flea beetles away from peppers, they protect cucumbers, squash and melons from cucumber beetles, and they rout two-spotted spider mites from tomato plants. If you want your radishes to stand guard duty, simply sow them among the plants they'll be protecting and leave them there. Plant a separate patch for harvesting and eating. Inc. How things get done. Use of this Web site constitutes acceptance of the eHow Terms of Use and Privacy .