This fall and winter vegetable is included in the Mustard family, Cruciferae, and is referred to botanically as Brassica oleracea gemmifera. The plant originated as far back as the 14th century near Brussels, Belgium, from which town it gets its name. The sprouts are miniature “cabbages” or “buttons,” each, when usable, about 1 1/2-2 in. in diameter, and are produced in the axils of the leaves around the stems of the plants. They are improved in flavor by light frost and are cooked as a green vegetable.
Soil Types. Brussels Sprouts, like most of the cabbage group of vegetables, thrive in soil that is rich in humus and is thus likely to be always reasonably moist. The soil must have good underdrainage, however, and may be from light sandy loam to heavy clay-loam. Failures may generally be attributed to periods of dry weather when insufficient supplies of water are given artificially. Fertile, deeply dug soil is all important and it is believed that heavy ‘clayey soils produce firmer sprouts than do light sandy types. In any case a moderately firm soil is necessary.
Seeds and Seed Sowing. Loose sprouts, instead of desirable tight “buttons,” may result from using a poor strain of seeds. Improved Long Island, growing to 20 in. tall, is a popular variety.
In areas where frost is unlikely after March, seeds may be sown outdoors as soon thereafter as the soil is sufficiently dry on the surface to tread upon without its adhering to the shoes. Sow in a shallow drill and cover lightly—oneeighth inch of soil above the seeds is ample. In 4-6 weeks the young plants should be large enough to transplant to their harvesting quarters; space them 18-24 in. apart in the rows and allow 24-30 in. between the rows.
In more northerly latitudes, where late spring frost is to be expected, seeds may be sown from early April to late May in a seedbed prepared with sifted soil in a greenhouse, hotbed, or other place where the temperature can be maintained at 50 degrees at night and where exposure to full sunlight is assured. When the seedlings show
their first true leaves they should be transplanted into flats or pots, or they may be planted 3 in. apart in a cold frame. About 6 weeks elapses from the time of seeding until the plants are ready for planting in the garden. Planting should be before the end of June. About 130 days are required from planting to the time when the first sprouts may be harvested.
Summer Care. A thorough soaking of water once a week is essential during spells of hot dry weather. Repeated cultivation will control weeds and conserve soil moisture but, since the roots ramify near the surface, shallow cultivating must be practiced. Mulching the soil surface with coarse compost or other suitable material may take the place of cultivating, once the plants are well established. Sprouts should be gathered as they become large enough for use—the lower ones first; they become tough if left too long. With late crops of Brussels Sprouts, cut off the lower leaves as the sprouts develop. If little time is left before severe frost, development of the sprouts may be hastened by removing the terminal bud from the stalk on which the sprouts grow.