Saving Seeds of the Brassicas (Broccoli, Brussels Sprouts, Cabbage, Chinese Cabbage, Kohlrabi, Mustard and Turnip)

Production readily produce flowers. Seed stalks may require staking for support. Brassicas (Brassica spp.) are one of the most important vegetable Isolation groups in the world. Most varieties are grown as temperate biennial All brassicas will cross with each crops, but tropical annual types are other. Cabbage, cauliflower, broccoli available. Brassicas prefer a cool and Brussels sprouts cross readily climate and temperature is the most with each other, as do radish, Honeybee pollinating brassica flower important factor for seed production. mustard, Chinese cabbage and Seed can be produced either by the turnip. Cross-pollination is done by head-to-seed method or seed-to- honeybees and an isolation distance Storage seed method. The following of 1000 m between varieties is describes the latter method, which recommended. Dried seeds can be safely stored for is used for tropical varieties that at least three years. Place seeds in jars, manila envelopes, cloth or require little or no cold weather to Selection induce flowering. mesh bags, plastic containers, or Off-type plants can be removed at foil envelopes. The best containers The planting time is critical. The are air-tight, such as a sealed glass crop should be raised such that the any time. Most growers rogue the field at the time of head/curd jar, metal can, or foil envelope. plants face the coldest temperature Protect seed from sunlight. at the time of maturity or head for- maturity so they can see the size, mation. A long cool season is also shape and firmness of heads/curds. Store seeds in a cool (below needed for seed pod development. 15 °C is ideal), dry location. Place Crops are typically sown/trans- Harvesting the seeds in a refrigerator for long- planted in early to mid-fall so that term storage. For short-term stor- plants are heading in late fall, bloom- Brassica seed shatters easily. age, keep the seeds in a cool, shady Harvesting is done carefully when 60– ing in early winter, and developing and dry place. 70% of the pods have turned brown seeds through the rest of winter. and most of their inner seeds are Special techniques may be used light brown and firm. References to facilitate the emergence of seed Kelly, A.F. and R.A.T. George. 1998. stalks. For cabbage, an “X” cross- Processing Encyclopaedia of seed production of cut is made at the top of the mature world crops. New York: John Wiley & head, being careful not to damage Harvested seed stalks are cured for Sons. the growing point of the inner core. 1–2 weeks. Pods are then threshed Rashid, M.A. and D.P. Singh. 2000. A manual of seed production in Bangladesh. A scooping slice may be done to with sticks and sifted by hand. Seed AVRDC-USAID-Bangladesh Project. the mature curd of cauliflower. The is brittle and should not be crushed Joydebpur, Gazipur, Bangladesh. tops of mature Brussels sprouts when handled. Seed is dried in partial plants are clipped to promote flow- sun, then cleaned and stored. ering. Other tropical brassicas will

Excerpt from “Saving your own vegetable seeds—a guide for farmers”. This fact sheet was written by Tom Kalb of AVRDC and Sutevee Sukprakarn, Sunanta Juntakool and Rukui Huang of Katsesart University. Photo by Ming-che Chen. AVRDC Publication No. 06-656. Published by AVRDC—The World Vegetable Center; P.O. Box 42, Shanhua; Taiwan 74151; ROC. April 2006. tel: (886-6) 583-7801; fax: (886-6) 583-0009; email: [email protected]; web: www.avrdc.org