Turnips are a cool-weather root vegetable that grow quickly in spring and fall.
There is a long tradition of growing turnips for feeding livestock, however turnips for human consumption may be grown for its bulbous roots or nutritious greens.
Aside from being high in dietary fibre and vitamin C, turnip roots have little nutritional value compared to its greens. Turnip greens contain significant concentrations of vitamins A, B, C, and K, as well as calcium and lutein (an antioxidant).
Turnips can be eaten raw, baked, boiled, roasted, or mashed. Prepare turnips as you would carrots. Turnip roots are commonly used in soups or stews, whereas turnip greens are cooked or used in salads.
Timing: Direct sow just after the last frost date where optimal soil temperature for germination is 18-21°C (66-70°F). The secret to planting successful turnips is speed. Sow short rows every 2-3 weeks, thin them quickly, keep them watered. Seeds should sprout in 7-14 days.
Sowing: Turnips are easy to grow in the garden but are not suitable for containers. Sow 5mm-1cm (¼-½”) deep, thinned to 15-20cm (6-8″) apart and in rows spaced 60cm (24″) apart.
Growing: Turnips are moderate to heavy feeders that does best in rich, loamy soil, amended with well rotted compost or manure. Dig in 1 cup of complete organic fertilizer for every 3m (10′) of row.
Lime beds before planting in the fall to bring the ideal pH level to 6.0 – 6.8.
Harvesting: After 40 to 55 days of planting, and once they have sized up adequately, gently dig the turnip from the ground. Do not let turnips sit in the ground any longer than necessary because the root maggots will destroy them.
When harvesting for both the root and the leaves, the turnip should be about 2” in diameter. Harvest turnips when they are smaller for a milder, sweeter flavour.
If harvesting for the leaves only, cut them from the plant once they have reached the desired size, leaving 1” of leaves above the crown of the plant for continuous growth. Select the smallest, youngest leaves for the best flavour, as more mature leaves tend to be bitter.
Pests and Disease: Avoid planting turnips where other Brassicas have been grown in the past 4 years. This crop rotation will prevent nearly all diseases from occurring.
Protection: Cabbage root maggot is a little fly that lays eggs on the soil where the stems of all brassicas emerge from the ground. Utilize a floating row cover to protect the directly seeded crops from cabbage moth and flea beetles.
Companion Planting: Turnips benefit best from mint and pea companions.
Turnips may be stored up to 3 to 4 months in a cool dark place such as a root cellar or in the refrigerator for up to 2 weeks. Remove the greens and clean off any soil before storing in a container covered with a damp cloth. To store the greens, wrap in a damp towel or paper towel in an airtight container.
Be sure to check your turnips regularly for spoilage and moisture, which causes rot, or dryness that could cause them to harden and split.