How to grow brussels sprouts
Family Brassicaceae. Hardy to USDA hardiness zone 3a+ (U.S. Department of Agriculture). Full sun. Ready in 90-130 days.
Sun
Full sun
Spacing
18-24 in
Days to harvest
90-130 days
Hardiness
Zone 3a+
What growers actually recorded
Loading zone 7b results…
When to plant brussels sprouts
- Start indoors: ~6 weeks before last frost.
- Transplant out: ~2 weeks after last frost.
Companion plants for brussels sprouts
Plant with: Dill, Onion, Thyme, Beet.
Avoid near: Tomato, Strawberry, Pole bean.
Common pests & problems
Aphid clusters in the sprouts, cabbage worm, cabbage looper.
Feeding & fertilizer
N-P-K ratio: High N (10-5-5): heavy feeders
Organic options: Aged manure or compost worked in deep · Blood meal or feather meal side-dress at 3 wks · Fish emulsion every 2 wks
When to feed: Feed heavily every 2-3 weeks. Brassicas want steady nitrogen for tight heads.
Watch for: Pale/yellow leaves = needs N. Loose heads = feed harder next round.
N = nitrogen (leaves), P = phosphorus (roots and flowers), K = potassium (fruit and disease resistance). How to read a fertilizer label →
Grower's tip
This is a fall crop: frost is what turns the sprouts sweet. Around 4 weeks before harvest, top the growing tip so the plant pushes size into the sprouts.
When to plant brussels sprouts in your zone
Free month-by-month sowing and transplanting lists, built from frost dates for your USDA (United States Department of Agriculture) hardiness zone.
Soil & water for brussels sprouts
Soil & pH
6.5-7.5: near neutral (raises club-root resistance)
Fertile loam with strong drainage. Firm soil beats fluffy for heading brassicas.
Compost 2 in + 1 cup of alfalfa or feather meal per 10 sq ft. Lime if pH is under 6.5. It also blocks club-root.
Watering
1-1.5 in / week, consistent
Ground-level drip. Uneven water during heading = split heads or bolting.
Lift an edge of the row and check soil at 3 inches. If it clings in a damp ball, hold off. If it crumbles, water until the top 6 inches are evenly moist.
Knowing when to harvest
- Sprouts are firm and 1-1.5 in across, starting from the bottom of the stalk upward.
- Snap off lower sprouts by hand once firm; leave upper ones to size up.
- Flavor improves noticeably after a light frost, which converts starches to sugars.
Storing & keeping
Leave on the stalk in a cool garage or refrigerate loose sprouts at 32-40°F, 95% humidity for 3-5 weeks. Blanch and freeze for storage beyond a couple months.
What to expect
Per plant: 1-2 lb, 50-100 sprouts per stalk
Troubleshooting brussels sprouts
Loose, leafy sprouts instead of tight buds
Likely cause: High nitrogen or hot weather during sprout formation
What to do: Reduce late-season nitrogen and grow as a fall-maturing crop timed to size up in cool weather.
Sprouts stay small
Likely cause: Crowded spacing or the plant not topped
What to do: Space 18-24 in apart; pinch out the top growing point 3-4 weeks before first frost to push energy into sprouts.
Aphid colonies inside sprouts
Likely cause: Aphids sheltering between tight leaves
What to do: Soak in salted water before cooking to flush pests, and spray insecticidal soap early in the season.
Varieties worth growing
Long Island Improved
Compact heirloom stalk suited to smaller gardens.
Diablo
Vigorous hybrid that holds up well in cold, extending the harvest window.
Falstaff
Red-purple sprouts with distinct color, best for fresh eating.
Growing brussels sprouts in containers
Poor container crop: the tall stalk needs a deep, heavy pot (15+ gallon) and a long, cool season, more than most containers can reliably support.
Nutrition
Sulforaphane, glucosinolates, vitamin K, calcium. Brassicas are the vegetable powerhouse.
Common questions
Should I remove lower leaves as sprouts form?
Yes, once a sprout below a leaf has sized up, snap the leaf off. It redirects energy and improves airflow.
Why do my sprouts taste bitter?
Harvested before frost, Brussels sprouts are notably more bitter. A frost or two sweetens them by converting stored starch to sugar.
Where these numbers come from
- USDA Plant Hardiness Zone Map (2023 revision). Zone assignment and the 30-year normals behind every cold-hardiness figure.
- NOAA NCEI 1991-2020 Climate Normals. Frost dates, growing-season length, and the probability bands on both.
- Cornell, UMN, and UC Davis Cooperative Extension crop guides. Spacing, days to maturity, soil pH targets, and per-plant yield ranges.
- USDA FSIS / FDA Produce Safety guidance. Wash, cure, and cold-storage handling numbers.
Ranges are regional guidance, not a promise for your yard. Your own logged results always override the published range.