Turnip, Brassica Rapa, is a herbaceous annual or biennial plant belonging to the Brassicaceae family. It has been cultivated as a cool-season vegetable for thousands of years for its edible leaves and roots. Historians believe that turnips originated somewhere in middle and eastern Asia. Today, they are grown in most temperate parts of the world for human consumption and livestock fodder. The plant forms short stems above the ground that bear light green leaves in the form of a rosette above the root. The taproot is round and plump with a combination of purple and white on the outer skin. Though it is a biennial plant that flowers and sets seeds in the second growing season, when turnip gardening the plants are often grown as an annual in early spring or fall and harvested after one growing season.
Types & Varieties of Turnip
Though you might have only seen half purple, half white tennis ball-sized turnips in grocery stores, there are tons of varieties beyond that. There’s a range of colors, sizes, and shapes to select from besides the flavors of roots and leafy tops and the time they take to reach maturity.
Common Varieties of Turnip:
Purple Top White Globe – This is the standard turnip variety that you find in grocery stores. It forms a 4 to 6 inches wide globe underground with a white bottom and a purple top. It takes between 50 to 55 days to reach maturity and has a spicy flavor that works well in stews and broths.
Baby Bunch Turnips – With small globular roots, about 1 inch in diameter, baby bunch turnips are harvested when they are still much younger than standard turnips. The crunchy flesh is similar to radish and works great in salads and cooked recipes.
Tokyo Cross – This hybrid variety is an AAS winner for the uniform, fast-maturing turnips it produces with mildly sweet and crispy flesh. The turnips are 3 to 6 inches wide white globes that are ready to be picked in just about 30 to 35 days.
Scarlet Queen – Different from others, this is a hybrid variety that produces turnips with bright red skin and white flesh. The turnips are slightly flat from the top and are harvested in 40 to 45 days.
For a self-sufficient garden, grow 5 to 10 turnip plants per person, spacing them 5 to 8 inches apart in rows. The rows should be spaced 15 to 24 inches apart.
Temperature and Timing for Growing Turnip
Turnip is a cool-season crop, best planted in early spring or fall when the temperatures are cooler. They take between 1 to 2 months to harvest and grow best when temperatures are between 40 to 70°F. For early season turnip gardening, you can sow the seeds in the ground 2 to 3 weeks before the last spring frost for harvesting in late spring. You can also plant them in late summers for an autumn harvest and in late autumn for a winter harvest.
Sun Exposure and Soil Requirements
Turnips thrive in full sun but will also grow well in partial shade. Well-drained, fertile soil with pH slightly on the acidic side (5.5 to 6.8) is best for turnip gardening. Prepare the planting bed well in advance by incorporating plenty of compost or aged manure. If your garden soil is heavy or clayey, amend it with sand or gypsum for the roots to develop easily.
How to Plant Turnip
For turnip gardening, just like any other root vegetable, turnips don’t transplant well. They are best planted by sowing the seeds directly in the garden once the weather is favorable. Although nursery transplants are available, most gardeners grow turnips by sowing seeds in the garden as soon as the soil is workable in early spring or 2 to 3 weeks before the last expected frost date.
The seeds are sown ½ inches deep in the ground and 1 inch apart in rows. Space rows 15 to 24 inches apart. Once the seedlings emerge and are 3 to 4 inches tall, you can thin them to maintain a 4 to 6-inch gap between the plants. The thinned seedlings make an excellent addition to salads.
Water well right after planting and keep the soil evenly moist throughout the growing season. Underwatered turnips will produce small and woody roots and may also cause the plants to bolt. On the other hand, overwatering promotes diseases, so it’s important to maintain just the right level of moisture. Mulching can help maintain optimal moisture in the soil for the plants and also protects the turnips from frost damage. Since turnips have a rather short growing season, they don’t generally need any fertilization, especially if you grow them in rich, fertile soil.
For a prolonged harvest season, you can practice succession planting every 10 to 14 days, keeping in mind that they can come to harvest before the temperatures soar above 70°F.
Since turnips are small plants, you can easily grow them in containers. Small roots can grow in pots that are at least 8 inches deep. For larger varieties, you’ll need to choose bigger containers.
As the growing season approaches a successful end, the plump turnips roots are ready to be picked from the ground. Here’s how to harvest turnips:
- You can start harvesting the leaves and stems once they are at least 12 inches long but allow the roots to develop further. However, only remove the outer leaves, letting the inner leaves to continue growing and producing the energy that will fuel root growth.
- Depending on the variety, turnips take between 30 to 60 days to come to harvest after sowing the seeds.
- As the turnips approach harvest, their purple shoulders will push out of the soil and are visible above the ground.
- Lift the roots from the ground using a garden fork once the shoulders are 2 to 3 inches wide. Take care not to puncture the roots with your gardening tools.
- Fall crop should be harvested after a few light frosts but before a hard freeze since extreme cold can cause the roots to crack or rot.
Turnip greens will only stay fresh in the refrigerator for up to a week. The roots can last for months if you store them properly. The ideal temperature for storing turnips is between 32 to 35°F. A small harvest can be stored in the fridge, but if you have lots of turnips to store, a cool, dark place such as a root cellar or garage will be ideal. Remove and consume the green tops before storing the turnip roots since the leaves will continue drawing energy from the roots if left attached to them.
Pest and Diseases
- Caterpillars, including cabbage loopers, diamondback moths, and beet army worms love eating turnip leaves. The most straightforward approach to get rid of them is to handpick and destroy them. Alternatively, you can spray the plants with Bacillus thuringiensis.
- Aphids suck the sap from the leaves of turnip plants, leaving behind a sticky substance called honeydew that promotes the development of molds on the plants. Small infestations can be catered to by removing the infested leaves. In the case of large infestations, hose them off with water or spray the plants with neem oil.
- Root maggots attack the roots and are, therefore, more problematic than other pests. The flies of these worms lay eggs around the plants. The larvae feed on the roots, leaving tunnels in the flesh and causing the plant to shrivel and die. Remove and destroy the infested plants to prevent the spread to the surrounding plants.
- White rust fungus can affect turnips and is observed by the development of white spots on the upper surface of the leaves and yellow spots on the underside. The disease is not serious, and the roots typically remain unaffected. Buy disease-free seeds and plant them in a well-drained garden bed free from any previous season’s debris.
- Downy mildew can affect turnip crops in cold conditions and is a serious disease because it can destroy the roots. It is identified as yellow, brown spots on the leaves that expand as the disease progresses. Preventive fungicide sprays can control the spread to other plants if you suspect the disease in your garden. Control weeds and excessively moist conditions to prevent the disease from occurring in the first place.
That’s all the information about turnip gardening that you’ll need to get started on your own. Follow all the tips and enjoy loads of juicy, spicy homegrown turnips!