ROOTS and TUBERS

The root and tuber crops are all perennials or biennials because of the storage root. The perennials contain large amounts of starch, which is their chief contribution to the diet, while the biennials contain very little. The perennials generally contribute some protein to the diet as well as starch, but this varies among species. Roots and tubers generally contain vitamin C, but only carrots and sweet potatoes contain useful amounts of vitamin A. Many roots and tubers contain toxic substances or antinutritional factors. As a general rule, it is best to cook them before eating. Roots and tubers are extremely important crops on a worldwide basis and should be included on every farm.

The roots are eaten either raw or cooked. The tops can also be eaten although not as common. Carrot seed germinates best in soil that is 10-30˚C (50-85˚F). Carrots too close will not develop a large taproot. This is generally a temperate crop, but the variety ‘Uberlandia’ does well in the tropics. Optimum soil pH: 5.8-6.8.

Choctaw: (Imperator Type) An early producing variety, 9-11 inches long root. Widely adapted, does well under stressful conditions. Smooth roots, good color. Resistance to alternaria and cercospora (causes foilage dieback). Hybrid.

Danvers 126: (Danvers Types) A midseason variety that is durable, bolt hardy, and strong tops. A multi-purpose carrot that is 7-8 inches long (root). Open pollinated.

Uberlandia: Tropical carrot variety which sets seed in one year. Harvest crop before seeds set, but allow a few plants to go to seed. Sow shallowly and thin as needed. The flavor has been judged as less than some of the other temperate carrot varieties that ECHO offers. A good carrot for those interested in breeding for certain traits.

B8542: Good heat tolerance, plus excellent resistance to major root-knot nematodes found in warmer climates. Higher carotene content than in the average carrot. From the USDA (United States Department of Agriculture.)

Leguminous plant with a tuber eaten raw as a snack or in salads; also remains crunchy when cooked; low nutritional value; requires short days for tuber production; leaves and seed toxic because contain rotenone. Produces well in hot, humid environments with a long, warm, frost-free growing season. Can be trellised and prefers well-drained soil. Optimum soil temperature: 6.5-8.

A cool weather crop that should be planted at the beginning of the cool season or the end of the hot season. Generally a quick crop from seed to harvest (30-45 days). Because of the short duration of the crop, it can be grown in the short dry season in some tropical areas. The roots are eaten, but the tops can be eaten as a cooked green vegetable. Tops can also be used as animal feed. Soil pH: 6-7.

Daikon: Also called Japanese radishes, these are primarily white-skinned. They are generally larger, coarser, larger to mature, and store well.

Cabernet: Hybrid radish. Dependable, crisp flech, and is adaptable to most growing regions. Top height 3.5-4.5 inches (8.75-11.25 cm).

Champion: Bright red radishes with strong tops for upland soils. Good for bunching and shipping. Open pollinated. 28 days until harvest.

Because seed tubers can spread viruses and are difficult to store in warm environments, true potato seed (TPS) offers several advantages over seed tubers. Potatoes will not produce tubers when soil temperature is above 80 F. Maximum tuber formation occurs between 60-70 F (18-21 C). Also they will not produce tubers if the difference between the day and night temperatures is less than 10 Fahrenheit degrees (5.6 centigrade degrees). This crop is also sensitive to day length. Potatoes will set tubers during long days. One disadvantage of TPS is they require a longer growing season. It is recommended to start TPS indoors for about 6 weeks before transplanting. Optimum soil pH: 5-6.2.

Catalina: medium/late maturity. Produces flat oval, fairly large, very uniform and attractive tubers with smooth white skin and shallow eyes.

Zolushka: medium early maturity. Produces round-oval, medium to large tubers of uniform shape, shallow eyes, smooth white skin. Yield is good to very good.

Cowpea relative with edible tubers. Used also as a cover crop to improve the soil and helps to control erosion by growing rapidly. Can also be used as a forage crop. Tolerates water logged soils for a period of up to six months. Optimum soil pH: 5.5-6.5.