How to Grow Brussels Sprouts in Winter
Brussels sprouts thrive in cooler temps, so sowing and planting them at the appropriate time is imperative. Brussels sprouts are planted later than warm-season crops, such as peppers and squash, from late fall into winter harvest. Depending upon the variety, Brussels sprouts take from 3-6 months to mature from seed. Start seed indoors about 16-20 weeks prior to the last frost in your area. Transplants are ready for the garden 12-14 weeks before the last frost in spring. For fall harvest, Brussels sprouts are planted in late May through early July. If you are growing Brussels sprouts over the winter in very mild areas, plant the crop in early autumn for a late winter to early spring harvest. Depending on your timing, opt for early varieties such as Prince Marvel, Jade Cross, and Lunet, which mature within 80-125 days from seed and are ready for harvest in the fall and early winter. In western areas of USDA zone 8, late-maturing varieties are suitable for winter growing and will be ready to harvest from December through April. These include: Fortress, Stablolite, Widgeon, and Red Rubine. While Brussels sprouts can be directly sown, due to timing and weather, success is more probable if you start them indoors. Transplants should be spaced 18-25 inches (45.5-63.5 cm.) apart in rows that are 2-3 feet (61-91.5 cm.) apart in a full sun area with good drainage, fertile soil and high in calcium with a pH around 5.5 to 6.8. Be sure to practice crop rotation to minimize the incidence of disease. Do not plant in the same area as other cabbage members in the previous three years. Because Brussels sprouts have shallow roots and top-heavy heads, provide some sort of support or staking system for them. Brussels sprouts are heavy feeders and should be fertilized at least two times during the growing season. The first time is when they are first planted. Fertilize with a high phosphorus food. Apply a second dose of fertilizer that is rich in nitrogen several weeks after. High-nitrogen foods include liquid fish emulsion, blood meal, or just a commercial fertilizer high in nitrogen.
Do Brussels Sprouts Need Winter Protection?
As mentioned, Brussels sprouts do very well in areas of the Pacific Northwest with its mild weather conditions (USDA zone 8) and can be grown in the winter. In USDA zone 8, very little winter care is required for Brussels sprouts. Brussels sprouts can also be grown in USDA zones 4-7 but with harsher winters, but caring for Brussels sprouts in winter requires a greenhouse. They are cool-season veggies and can withstand freezes for short periods of time, but sustained cold snaps and burial in the snow won’t result in winter sprouts. In colder climates, Brussels sprout plants should be pulled out of the soil before temps drop below 10 degrees F. (-12 C.) in the late fall. They can then be stored in a cool, dry area with their roots buried in a box of damp sand. In milder areas, where temperatures rarely dip below freezing for an extended period of time, caring for Brussels sprouts in winter requires little effort. My neighbor here in the Pacific Northwest simply rakes up everything in her yard in the fall and mulches around the plants with the fall leaves. So far, she has had beautiful standing plants with fresh Brussels sprouts ready for harvest during the winter holidays.
