Brussels sprouts

About Brussels sprouts

Brussels sprouts form rows of little cabbage-like buds up a tall stalk. They need a long season and are at their best in fall, since cool weather and light frost make the sprouts sweeter.

Grown as a cool-season annual in every zone. It is usually timed to mature in fall, and plants can stay in the garden as long as temperatures stay above about 20F.

When to plant

Timing is counted from your average last spring frost (and first fall frost). Sow & Tell works out the actual dates for your ZIP code.

• Start seeds indoors: 6 to 10 weeks before the last frost
• Set out plants: 2 to 4 weeks before the last frost
• Fall planting: 10 to 14 weeks before the first fall frost

Days count from setting out transplants; direct-seeded plants can take up to 3 weeks longer. Start seed indoors 4 to 6 weeks before transplanting. In the North it is mostly grown as a fall crop from transplants set out in early summer.

Soil

Fertile, well-drained soil that still holds moisture; water thoroughly about once a week.

Work in compost or well-rotted manure, follow a soil test for phosphorus and potassium, and aim for soil pH about 6.2 to 6.8.

Feeding

• when plants are about 12 inches tall: nitrogen fertilizer. Side-dress beside the row and water it in.
• every 3 to 4 weeks after that, while sprouts are forming: nitrogen fertilizer. Repeat a light side-dressing to keep plants producing; water it in.

Do not use fresh manure or weed-and-feed products, and skip extra phosphorus unless a soil test calls for it.

Harvest

Pick sprouts from the bottom of the stalk up, starting when the lowest ones are about an inch across. Flavor improves after the first frosts.

Sprouts form and fill from the bottom of the stalk up, so pick the lowest ones first over several weeks; cutting off the top 1 to 2 inches once the lowest sprouts are an inch wide helps the top ones size up. When temperatures reach the mid-20s F, cut whole stalks and store them in a cool place to keep picking for a few more weeks.

Varieties (17)

Good neighbors

Sage, Thyme, Arugula, Mustard greens

UMN Extension cites a greenhouse study where sage and thyme reduced diamondback moths on Brussels sprouts, and notes arugula and mustard as flea beetle trap crops; field results are less certain.

Pests to watch for

Flea beetles, Imported cabbageworm, Cabbage looper, Diamondback moth, Cabbage maggot, Aphids, Swede midge, Bagrada bug, Voles

Diseases and problems

Black rot of cabbage-family crops, Clubroot, Alternaria leaf spot (cabbage family), Verticillium wilt, White rust, Turnip mosaic

In the kitchen

Roasted, sauteed or shaved raw into salads.

Keeping it: Refrigerate unwashed sprouts in an airtight bag for about a week. In very cold, humid storage they can keep about a month.

Pets: Not listed as toxic by the ASPCA