How to Grow Brussels Sprouts 'Long Island Improved'
Brassica oleracea var. gemmifera 'Long Island Improved'
Brussels sprouts 'Long Island Improved' are a reliable cool-season brassica prized for their sweet, nutty flavor that develops best in crisp autumn weather. Gardeners grow these hardy plants to harvest rows of miniature cabbages along sturdy stalks, adding vibrant green color and essential nutrients to winter meals.
📷 Wikimedia CommonsStarting Brussels Sprouts 'Long Island Improved': indoors or direct sow?
🌾 Sow directly in the garden — Brussels Sprouts 'Long Island Improved' is not usually started indoors.
Direct sow seeds outdoors or transplant seedlings carefully once they have hardened off and soil temperatures are cool enough for brassicas.
Soil, care & harvest
Prepare your soil by loosening it deeply and amending with compost to ensure good drainage within the preferred pH range of 6.0 to 7.0. As a cool-season crop, start seeds indoors 8 to 10 weeks before the last spring frost or direct sow them 2 to 6 weeks prior. Plant seeds about one inch deep; they typically germinate within five to ten days once soil temperatures are right.
Space plants 18 to 24 inches apart in rows to allow proper air circulation and growth. While these varieties generally do not require support, ensure the soil remains consistently moist with about one to 1.5 inches of water weekly. Apply a layer of mulch around the base to retain moisture and suppress weeds, feeding lightly if growth seems sluggish.
Watch for cabbage worms, aphids, flea beetles, and loopers; use row covers or insecticidal soap early in the season to prevent infestations. Monitor for clubroot, black rot, downy mildew, and powdery mildew by ensuring good airflow and avoiding overhead watering when possible. Harvest begins roughly 100 days after sowing, picking individual sprouts as they mature from the bottom of the stalk upward.
When to Plant Brussels Sprouts 'Long Island Improved'
Planting windows vary by USDA hardiness zone. Look up yours by ZIP code.
| Zone | Start Indoors | Direct Sow | Harvest |
|---|---|---|---|
| Zone 1 | April – May | June – July | September |
| Zone 2 | April – May | May – July | September |
| Zone 3 | March – April | May – June | August – October |
| Zone 4 | March – April | April – June | August – October |
| Zone 5 | February – March | April – May | August – November |
| Zone 6 | February – March | April – May | July – November |
| Zone 7 | February – March | March – May | July – November |
| Zone 8 | January – February | March – April | June – December |
| Zone 9 | January | February – March | May – December |
| Zone 10 | January | January – March | May – December |
| Zone 11 | January | January – February | April – December |
| Zone 12 | January | January – February | April – December |
| Zone 13 | January | January – February | April – December |
Companion Plants for Brussels Sprouts 'Long Island Improved'
✓ Good companions
Different root depth prevents competition, may improve soil structure
Loosens soil around Brussels sprouts roots, doesn't compete for nutrients
Natural pest deterrent that repels cabbage worms and aphids
Attracts beneficial wasps that parasitize cabbage worms
Deters nematodes and general garden pests, attracts beneficial insects
Acts as trap crop for aphids and flea beetles, repels cucumber beetles
Repels cabbage root flies, aphids, and other brassica pests
Repels cabbage worms and whiteflies, attracts beneficial insects
✗ Keep away from
Same family (Brassicaceae) attracts identical pests and diseases, depletes soil nutrients
Inhibits Brussels sprouts growth and development through root competition
Both are heavy feeders competing for nutrients, tomatoes may stunt brassica growth
Nutrition Facts
Per 100g serving (USDA FoodData Central)
