When to Harvest Turnips:
• Harvest turnips when root tops are 1 to 1½ inches in diameter but not more than 2½ inches in diameter.
• Turnips that get too big will be strong flavored and often become tough and fibrous.
• Harvest turnip greens young and tender. Cut the outer leaves an inch or so above the crown and the leaves will grow back quickly. Don’t cut too many leaves or you will slow root growth.
• Turnip roots are ready for harvest 40 to 50 days after sowing.
Turnips are cool-season plants that grow best at temperatures between 60° and 65 °F (15-18°C). Turnips do not grow well and flavor will suffer if grown where daytime temperatures are consistently greater than 80°F (26°C).
Where winters are mild and the soil is well drained, leave turnips in the ground until you need them but harvest them before they start growing again in spring.
Turnips can take top frosting, but where the ground freezes, lift root before the soil freezes. A freeze will yellow and wither turnip greens.
How to Harvest Turnips:
• It’s best to pull turnips when the soil is dry. Pull or lift roots carefully from the garden so as not to break or injure them. Use a garden hand fork to loosen the soil around the roots if necessary.
• Twist off the greens after lifting the roots. Removing the tops before storage will greatly extend storage life.
How to Store Turnips:
• Store the best turnips; damaged or bruised roots will not store well and should be eaten soon after harvest. Gently rub soil from the roots before storing them. Don’t wash roots before you store them; if you do, be sure to dry them thoroughly.
• Store turnips in a cold moist place as near to freezing as possible without actual freezing, 32°-40°F (0°-4°C) and 95 percent relative humidity.
• Store turnips wrapped in a moist cloth or paper towel in placed in a perforated plastic bag in the vegetable crisper drawer of the refrigerator. Turnips will keep in the refrigerator for 4 to 5 months.
• Store turnips greens just as you would turnip roots.
• If there is not room in the refrigerator, turnip roots can also be packed in a container—a bucket or plastic storage box or cooler–in moist sand, peat moss, or sawdust. Don’t pack roots too tightly; if the roots touch they can start to rot; be sure to leave 2 inches (5 cm) of insulating material around at the top, bottom, and sides of the stored roots. Set the lid loosely so that there is good air circulation and place the container in a cold place such as a basement, garage, or shed.
• Check roots in storage often and remove any that show signs of deterioration.
More tips: How to Grow Turnips.