Radishes and turnips are quick to mature and will develop quickly after winter days grow longer and temperatures rise in through the spring. An added benefit of overwintering radishes and turnips is their resistance to pests and disease.
These plants appreciate well-drained soil that is loosened from a foot to 16 inches deep. Select a turnip-growing site that will get full sun when spring season arrives.
Plant seeds about a half inch deep when the first frost occurs and cover with a layer of compost and a thicker layer of straw. That should be enough to protect them from winter’s cold.
Throughout the winter keep the soil lightly moist. Don’t allow it to get overly moist or else root rot will set in. Root rot causes deprives plants of oxygen and can kill the plants or stunt their growth. Be sure to keep these beds weed-free. As temperatures begin to climb and winter winds die down, you can remove the straw layer over your garden bed.
These plants will see an initial harvest after six to eight weeks of growing. Mature harvests will be available about two and a half months after growth begins. Water plants at an average one inch of water weekly. Once harvested, turnips and radishes will store about two to three months in a cool, dark place.