Turnips

Turnips and mustards, members of the cabbage family, are cool season crops. They must be grown in the cool temperature of early spring and late fall, and they need full sun and a well drained soil for best production. Mustard is grown only for the leaves. Turnip is a dual purpose crop. The leaves are used for greens and the root is cooked similar to potatoes and beets.

Soil Preparation and Fertilization

The soil should be free of large rocks, sticks and other bits of trash. If the soil is heavy clay, add compost or other organic matter to loosen the soil. This is very important if turnips are grown for the roots because heavy soil can cause turnip roots to be rough and poorly shaped.

Dig the soil 10 to 12 inches deep. Be sure all plant material is covered. This makes it break down quicker. After the soil has been dug, scatter 2 to 3 pounds of complete garden fertilizer such as 10-20-10 over each 100 square feet. If only one row is to be planted, use 1 cup of fertilizer for each 10 feet of row (see Figures 1A and 1B). Phosphorous, the middle number on the fertilizer bag, is especially important to grow good turnip roots.

Bed the soil into ridges 6 to 8 inches high and 18 to 24 inches apart (see Figure 2). Allow the ridges to settle or pack them before planting.

Planting

Turnips and mustards should be planted as soon as the soil can be worked in the spring. Mustard and turnip seeds will sprout if the soil temperature is 40o or higher. For a fall crop start planting 8 to 10 weeks before the first expected frost. In South Texas and coastal areas turnips and mustard grow well all winter.

Just before planting, drag the top off of the ridges with a rake or hoe. This widens the planting bed to 8 to 10 inches. It also allows the seed to be planted in moist soil (see Figure 3). This is very important when planting the fall crop.

If the ridges are made on 3 foot centers for planting other vegetables, two rows of mustard and turnips can be planted on each ridge. Plant one row down each side of the ridge.

Cover the seeds lightly with soft soil or compost. Sprinkle with water to speed sprouting. When planting for a fall crop, cover the seeds with sand or light colored mulch to keep the row cool. Sprinkle the row lightly with water to prevent soil crusting until the small plants break through. Under good conditions most of the plants should be up in 3 to 7 days.

To have a continuous supply of fresh, tender mustard and turnip greens, make two or three plantings 10 days apart.

Mustard and turnip should be planted in full sun, if possible. Mustard works well as a border to a flower bed or sidewalk. Both the broadleaf and curled leaf varieties are attractive and add green to a flower bed (see Figure 4). Mustard and turnip greens are easily grown in window boxes and containers on an apartment balcony or patio.

Varieties

Turnips can be used either for greens or for roots. A variety developed for root production can be harvested for greens. A variety developed for greens may not produce a good root. Most varieties produce greens in 40 days. From 50 to 60 days are usually required to produce turnip roots.

Mustard varieties can be broad-leaved or curled. Broad-leaved mustard has a wide, flat leaf. Curled leaf mustard produces more narrow, wrinkled leaves similar to spinach. Curled mustard will stand more cold and can be grown later into the winter than broad-leaved mustard. Some gardeners do not like curled mustard because it is hard to wash sand and dirt from the wrinkled leaves. A well-mulched garden usually does not have this problem.

TurnipsMustard
GreensRootsBroad-LeavedCurled Leaf
Shogoin
Seven Top
Purple Top White Globe
Tokyo Hybrid
Just Right Hybrid
Tendergreen
Florida Broadleaf
Curled leaf
Southern Giant Curled

After Planting

Keep the plants free of weeds especially when they are small. Pull the weeds by hand or use a hoe. Do not cut too deeply with a hoe or some crop roots may be cut.

Soak the rows with water each week if it does not rain. Water may be needed more often in some areas. Soak the soil well to develop a good root system.

When the plants become crowded in the row, thin them by pulling some plants. Small plants of both turnips and mustard make delicious greens. Thin mustard plants until they are 6 inches apart. Leave turnips 3 to 4 inches apart. Overcrowding prevents turnip roots from developing (see Figure 5).

Turnips and mustards need adequate nitrogen to develop dark green color. When the plants are 4 to 5 inches tall apply 1/2 cup of fertilizer for each 10 feet of row. Spread the fertilizer beside the plants, mix it lightly with the soil and water it into the soil. If your soil is sandy and the season is wet you need to apply more fertilizer later.

Insects

Name and DescriptionControl
1/8 inch long; soft bodied; green, pink, red or brown; underside of leaves; suck plant juices.Malathion
1/18 inch long; bronze black, blue or green; jump quickly; eat small holes in leavesSevin
Up to 1 1/2 inches long; pale green with light stripes down back; doubles up or loops when it crawls; chews leavesBacillus thuringiensis (Dipel, Thuricide, Biotrol)
1/4 to 1/3 inch; yelowish white; legless; feed on turnip rootDiazinon

Before using a pesticide, read the label. Always follow cautions, warnings and directions. Since greens are harvested often, be sure to follow waiting periods for pesticides.

Diseases

Diseases can be troublesome when the weather is cloudy and damp. If plants begin to look weak and unhealthy, diseases may be present. Your county Extension agent can help you select a good fungicide to use for disease control.