Brussels sprouts can be grown in just about any home vegetable garden if you have patience. Brussels Sprouts plants require a very long growing season. However they actually taste better when they are hit with a slight frost, so although they are a late harvest, they are a relatively long one.
Because of their fondness for cool weather, Brussels Sprouts are a fall crop in warmer climates. As with broccoli, growing Brussels sprouts in warm weather and long days will cause the “sprouts” to open and be unsuitable for eating.
Named after the city of Brussels, Brussels sprouts were first made popular in Belgium, where they’ve been grown since about 1200. The sprouts are buds that grow in the axils of each leaf. They look like tiny cabbages and are actually considered a type of wild cabbage. The plant itself looks like a small palm tree and the sprouts grow along the trunk-like stem. The green variety is the most commonly grown, but there are red Brussels sprouts too.
USDA Hardiness Zone
Mature Plant Size
Brussels sprout plants reach a size of 2 - 3 ft. (60 to 90 cm) tall x 8 - 12 inches (20-30 cm) W. The sprouts are about 1- 1 ½ inches (25 to 40 mm) in diameter, but you can start to harvest them when they are smaller.
The plants will grow and sprout best in full sun to partial shade.
Days to Harvest
You will have to be patient. Brussels sprouts take about 3 months, from transplant, before you can begin harvesting. They grow tall first and don't start producing sprouts until they reach almost full height.
Brussels Sprouts Growing Tips
Soil: Brussels sprouts like a sweet or slightly alkaline soil. The soil pH should be at least 6.5, but preferably higher. A good amount of organic matter will help maintain the moisture they need for their intense growth.
When to Plant: In colder climates, start Brussels sprouts seeds indoors and set outside when there’s no threat of a hard frost. Be sure to allow the full time outdoors for required days to harvest.
In warmer climates, fall planting is preferred. You should be able to direct seed in mid-summer for a late fall/winter harvest. You may also be able to squeeze in a second, early spring crop, direct seeding in February and harvesting in May. Hot climates where the temperature never approaches freezing are not really suitable for growing Brussels sprouts.
Seeding: Direct sow in warm areas. Otherwise, start seed indoors approximately 5 - 7 weeks before last expected frost. Cover seeds with 1/4 - 1/2 inch of soil and keep moist. Transplant when the seedlings are about 3 inches tall. It is very important that you don’t allow the seedlings to become root bound or the plants will remain stunted when transplanted.
Transplanting: Brussels sprouts like the soil around them to be firm, but not compacted. Pat it down lightly.
Spacing: Space plants about 2 ft. apart with 3 ft. between rows or stagger plants 2 ft. apart in each direction, for a grid.
Feeding: Fertilizing Brussels sprout plants twice a season (once when the plants are about 12 inches high and again about a month before harvest) is often recommended, but if you have a fertile soil, to begin with, it doesn’t seem to be necessary. One dose of an organic, slow release, granular fertilizer will feed the plants most of the season.
Caring for Brussels Sprout Plants
Brussels Sprouts are prone to the same problems as cabbage and broccoli. The most common pests are Cabbage looper, imported cabbage worm, cabbage root maggot, aphids, and Harlequin bug. Since this is a late season crop, you have time to monitor for problems before the sprouts start forming.
Diseases include blackleg, black rot, and clubroot. Disease control is best obtained by rotating the crop each year. Clubroot is diminished when you raise the soil pH to about 7.0.
How to Harvest Brussels Sprouts
Each sprout grows in the leaf axil or joint. They begin maturing from the bottom of the plant upwards. You can start harvesting when the lower sprouts reach the size of large marbles. Just be sure to pick before they get too large and start cracking and turning bitter.
Pulling off the sprouts is made easier if you remove the leaf below the sprout first, then twist and pull the sprout. Some people prefer to cut, rather than pull the sprouts. Each plant yields approximately a quart of sprouts total.
After harvesting, a second crop of Brussels sprouts may begin to grow at the base of the stem. These will not be as tight as the first buds, but they are still edible.
The leafy tops are also edible and can be cooked as greens. Cutting the tops is a good way to speed up the development of the remaining sprouts, at the end of the season.
To extend your Brussels sprouts harvest in cold seasons, mulch plants with straw and/or cover with a row cover for protection. Whole plants can be pulled, potted and stored in a root cellar. Bare root plants stored in a cool cellar will give you an additional 2 - 3 weeks of harvest.
Some Great Varieties of Brussels Sprouts to Grow
- "Bubbles" F1 (85 - 90 days) Early and easy. Tolerates heat and drought. 2" sprouts. Resistant to Powdery Mildew & Rust.
- "Jade Cross" F1 and ‘Jade Cross E’ F1(90 days) Jade Cross was a 1959 All-America Selections Winner. Both are compact plants good for windy locations. Sprouts are slightly larger on Jade Cross E. Good disease resistance.
- "Long Island Improved" OP (90 days) High yield. Another small plant that stands up to wind. Freezes well.
- "Oliver" F1 (85 days) Early producer. Easy to pick, 1-inch sprouts. Compact, disease resistant plants.
- "Royal Marvel" F1 (85 days) Early and productive. Resistant to bottom rot and tip burn.
- "Rubine" (85 - 95 days) Purple plants. Late maturing and lower yield than green varieties, but good flavor. 1 ½ inch sprouts. Heirloom.