Can you tell me how cabbage plants make seed? Ken C.
Answer: Cabbage, broccoli, brussels sprouts, cauliflower, kale and kohlrabi are all the same species, Brassica oleracea. They all have the same seeding and pollination habit. These plants produce a flower stalk that needs to be cross-pollinated by insects (which means that they won’t accept their own pollen).
The cabbage plant sends this flower/seed stalk directly out of the cabbage core. This process is called “bolting“. Cabbage cannot bolt in the same year they are planted. They must be overwintered, replanted in the spring, and allowed to bolt.
Home growers should plant their cabbage so it will be mature at the end of the season. Then at least three firm, ready-to-eat heads need to be selected. Remove the plants, roots and all, and store in a root cellar, refrigerator or cold basement. Keep the roots damp and cool during the winter.
To get a cabbage plant to make seed, in the early spring you would replant the plants, leaving two to three feet in between them. They will produce the seed stalk directly from the center of the plant. Cabbage seeds ripen slowly and fall off immediately when they are ripe. So you might want to either harvest the whole plant as the pods turn yellow or pick the dry pods when they turn brown.
If you’re planting in an open garden and growing any other members of the Brassica family, it might be surprising what your seeds develop into. Since the plants can be cross-pollinated with broccoli, brussels sprouts, cauliflower, etc. But they might be interesting in flavor!
Good luck if you give this a try, and happy growing!