How to Manage Pests

Cultural Tips for Growing Radish

In This Guide

Site selection

Plant your garden in a convenient location, where you can check it frequently. Choose an area near an abundant supply of water so you can water as needed easily. Vegetables do best if they receive full sunlight (at least 4 to 6 hours a day). Plant them in a well-exposed area in the garden, where they are not shaded by trees, fences, or walls. Try to plant away from areas that will be watered by lawn sprinklers.

Whenever possible, select a location that is not heavily infested with weeds, especially weeds such as field bindweed, nutsedge, and Bermudagrass that can be hard to control with hand weeding. Also avoid areas that have had previous disease problems.

Try to plant on level ground. Level ground is easier to work on than sloping ground. Vegetables will do well on a wide range of soils; they do best in well-drained soils. If your soil forms a clump when squeezed, then it is too wet; if the soil crumbles easily, it is a good soil to use. Damp soil surfaces encourage snails, slugs, sowbugs, and root diseases; fruit decay and leaf spot diseases may also increase. Soil amendments can make clay and sandy soils easier to work with, and correct soil preparation can improve poor soil.

Adding organic matter (compost, peat moss, manure, sawdust, ground bark) makes clay and sandy soils easier to work with. The soil should be kept at a pH level of 6.0 to 6.5. Lime or gypsum can be added to soils low in calcium.

Soil recommendation

Deep, loose soils; sandy loam or soils with high organic content. Avoid rocky soil.

Soil improvement

Any type of soil can be improved with soil amendments. Heavy clay or sandy soils can be improved by adding organic material such as compost, manure, or leaf mold. Texture is an important consideration when choosing an amendment. An amendment that is granular and fine grained is important for container mixes. For gardens, a more coarse-grained amendment can improve drainage and aeration. Work amendments into soil by rototilling, raking, or double-digging.

Soil preparation

The preparation of your soil is just as important as adding fertilizer and soil amendments. Before working the soil, make sure it is moist but not thoroughly wet.

1. Use a shovel, rototiller, metal bow rake, or all of them together to loosen the top 1 to 2 inches of soil. Rake the area to remove weeds and old crop debris. Be sure to dig out roots.
2. Irrigate the plot deeply to encourage the germination of weed seeds.
3. In a week or two, after a substantial number of weeds have germinated, work the area again to kill the weed seedlings. Be sure to break up the clods in the soil, as seeds planted in cloddy soil will germinate poorly and won't live long because the soil dries too quickly.
4. Form soil into beds if desired, and plant while soil is still wet.

Time to plant

Radish is a cool season vegetable. Radishes grow best in cool temperatures off 50° to 70° F and relatively short days (10 to 12 hours). Above 80° F, bolting is common and roots are more often deformed.

Planting Radishes

Radishes can be grown from seed and should be thinned 4 to 8 inches apart depending on the size of variety grown. Larger varieties need more space. You can plant successive crops during the growing season for continuous harvest.

Fertilizing

Most vegetables require fertilizer for growth. Organic materials, such as manures and compost, and inorganic materials, such as chemicals, can be used to fertilize plants. Using both types of materials usually provides the best growth. Manures and compost can be used to increase soil fertility. They are usually applied at 1 pound per 4 or 5 square feet. These materials should be worked into the soil several weeks before planting in order to allow it to decompose. Manure that contains straw, sawdust, or similar materials should be applied with a commercial nitrogen fertilizer. Generally, if the soil has been properly amended with compost or manures or other organic materials, the only nutrient needed is nitrogen, if anything. Some commercial nitrogen fertilizers available are urea, ammonium sulfate, calcium nitrate, and ammonium nitrate. Apply these fertilizers at rates of 0.5 to 1 pound of nitrogen per 100 feet of row.

If manure and other organic material has not been used, apply fertilizer that contains both nitrogen and phosphorus before planting. All commercial fertilizers are labeled by the percentages of N-P-K; nitrogen (N), phosphorus (P), and potassium (K). Some common mixed fertilizers are 5-10-5, 5-10-10, 8-16-16, and 12-12-12. Apply these fertilizers at rates of 1 - 2 pounds per 100 feet of row. After plants are 3 to 4 inches tall, sidedress nitrogen in narrow bands or furrows and water thoroughly after application, or apply through the drip system. Consider light but frequent applications of nitrogen fertilizer every 3 to 4 weeks. Avoid letting the fertilizer come into contact with the plant stems to avoid burning.

Application tips

Inorganic fertilizers can be sidedressed. Manures are more difficult to use as a side dressing and must be tilled into the soil.

Banding: Make a small groove 1 or 2 inches deep on both shoulders of the bed, 4 to 6 inches from the plant row and band in the fertilizer. Replace the soil and irrigate.

Where drip or trickle tubes are used, apply fertilizer on the soil surface near the drip tube.

Watering Radishes

Examine your soil visually and with your hands to determine the need for additional water. Radishes need to be kept moist throughout the root zone for the proper growth. Dry soils or crusting, especially in the seedling stages, will impair root growth.

Proper watering with either drip or furrow irrigation will keep your plants vigorous and help protect them from insect damage and sunburn.

Harvesting and Storing Radishes

Radishes reach maturity and are ready for harvest in 3 to 6 weeks after seeds are planted, depending on the variety. Harvest right when radishes mature, when they are tender, by pulling up the whole plant. If left in the ground radishes may crack and become tough, fibrous, and more pungent. Trim the tops off the radish and store in the refrigerator if not using fresh. Winter radish varieties take longer to mature, but also keep longer in storage.