How to grow Brussels sprouts and when to harvest them

Brussels sprouts are a long-season crop. They take most of the growing season to mature, but the wait pays off. Sprouts picked after a few fall frosts taste sweet and nutty.

The sprouts grow like tiny cabbages along a tall, thick stem. One plant can give you dozens of sprouts.

When to plant Brussels sprouts

Brussels sprouts need about 90 to 110 days from transplant to harvest. Time them so the sprouts form in the cool weather of fall.

In cold-winter gardens, start seeds indoors 4 to 6 weeks before your last spring frost. Plant the seedlings out around your last frost date. They grow all summer and are ready to pick in fall.

In hot-summer areas, start seeds in early summer and plant out in midsummer. The sprouts then form in fall and winter, when it is cooler.

Where to plant Brussels sprouts

• Full sun, at least 6 hours a day
• Rich, well-drained soil with lots of compost
• A soil pH of 6.0 to 7.0
• A bed that did not grow cabbage-family crops last year

Rotating beds helps prevent clubroot and cuts down on pests.

How to plant Brussels sprouts

1. Work 2 inches (5 cm) of compost into the bed.
2. Space plants 18 to 24 inches (45 to 60 cm) apart, in rows 30 to 36 inches (75 to 90 cm) apart.
3. Set each transplant a little deeper than it sat in its pot.
4. Firm the soil around the stem and water well.
5. Cover with row cover to keep out cabbage butterflies and flea beetles.

Plants grow 2 to 3 feet (60 to 90 cm) tall. In windy spots, stake them or hill soil around the stems so they do not tip over.

Water and feeding

Brussels sprouts are heavy feeders. Give them 1 to 1.5 inches (2.5 to 4 cm) of water a week. Mulch keeps the soil cool and moist through summer.

Side-dress with compost or a balanced fertilizer about a month after planting, and again in midsummer. Do not overdo nitrogen late in the season. Too much can give you loose, leafy sprouts.

How to get bigger sprouts at the same time

Sprouts form from the bottom of the stem up. The ones at the bottom are ready first.

If you want the whole stalk to be ready at once, top the plant. About 3 to 4 weeks before you want to harvest, cut off the growing tip at the top of the stem. The plant stops growing taller and puts its energy into the sprouts.

As sprouts form, you can also snap off the lower leaves that turn yellow. That gives the sprouts more room and better airflow.

How to harvest Brussels sprouts

Pick sprouts when they are firm, tight, and 1 to 2 inches (2.5 to 5 cm) across. Start at the bottom of the stem and work up. Twist them off or cut them with a knife.

Do not wait too long. Sprouts left on the stem too long open up and turn yellow.

Brussels sprouts taste best after frost. Cold weather turns some of the starch in the sprouts into sugar. Mature plants handle frosts down to about 20°F (-7°C).

Before a deep freeze, cut the whole stalk at the base. Pull off the leaves and store the stalk in a cool place. The sprouts stay fresh on the stalk for a week or two. Loose sprouts keep for a few weeks in a bag in the fridge.

Best Brussels sprouts varieties

Variety	Type	Notes
‘Long Island Improved’	Heirloom	Compact, reliable, good for small gardens
‘Jade Cross’	Hybrid	Handles heat better than most
‘Diablo’	Hybrid	Big yields of uniform sprouts
‘Falstaff’	Open-pollinated	Red-purple sprouts that keep some color when cooked

Common Brussels sprouts problems

Problem	Likely cause	Fix
Loose, open sprouts	Heat while sprouts form, too much nitrogen, or loose soil	Time planting so sprouts form in fall, firm the soil
No sprouts	Planted too late or not enough time	Plant earlier next year, top the plants in fall
Holes in leaves and green caterpillars	Cabbage worms	Use row cover and hand-pick
Gray clusters inside sprouts	Cabbage aphids	Spray them off with water early, before they move into the sprouts
Plants tip over	Wind and tall stems	Stake plants or hill soil around stems

Here is more on how to get rid of cabbage worms and aphids on plants.

More cabbage family crops

Brussels sprouts grow the same way as their cousins:

• How to grow broccoli
• How to grow kale
• How to plant cabbage seeds
• How to plant cauliflower seeds