Long Island Improved Brussels Sprout

Family: Brassicaceae Brassica

Savory-sweet and deeply satisfying, Long Island Improved Brussels Sprout forms tight, jewel-like heads that turn rich green as the weather cools.

Expect a firm, crisp bite with a tender core—ideal for roasting to bring out a mellow, nutty richness, or for fresh braises and hearty skillet-style preparations. A classic cool-season favorite with dependable, uniform set over a long harvest window, it’s a rewarding choice for gardeners who love vegetables that taste even better after a chill.

Light: Full SunMaturity: 90 DaysHabit: Upright

Botanical illustration of Long Island Improved Brussels Sprout

Planting schedules and alerts are optimized for Columbus (Zone 6b).

Crop Dates

Milestone	Date
Start Indoors	Mar 21st
Last Frost	Apr 25th
Transplant / Sow Outdoors	Apr 25th
Harvest Begins	Jul 24th
Harvest Ends	Oct 16th

Crop Details

Trait	Value
Days to Maturity	90
Sun Requirements	Full Sun
Growth Habit	Upright
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	45
Min Soil Temp (°F)	40
Min Night Temp (°F)	28
Harden Off (days)	6

Culinary Notes

Chef's Note

These tight, uniform little heads are built for roasting: the outsides stay snappy while the centers go tender and nutty, not sulfurous. When you hit them with fat plus acid—like bacon/cheese/brown butter and lemon—they taste clean and deep, like winter comfort without heaviness.

Best Uses

high-heat roasting until the leaves bronze at the edges
quick skillet braise with a splash of broth/wine to soften the core
shaved or halved for sheet-pan crisping before finishing with butter or vinaigrette

Flavor Profile

savory-sweet, green and mildly nutty firm, crisp outer leaves with a tender core roasty, caramel-leaning sweetness when cooked

Kitchen Pairings

bacon or pancetta lemon zest garlic mustard (Dijon or whole-grain) parmesan brown butter

Frequently Asked Questions

What pest or disease most often affects Brassica oleracea var. gemmifera (Brussels sprouts), and what should I do first?

Watch for cabbage worms/loopers and aphids; on Brussels sprouts they chew leaves and can quickly defoliate plants. Inspect undersides weekly and hand-pick larvae, then spray an approved BT (Bacillus thuringiensis) treatment for caterpillars and use insecticidal soap for aphids. If you see yellowing with gray fuzzy growth, remove affected leaves immediately and improve airflow (don’t crowd plants), because Brussels sprouts can be prone to fungal leaf issues in damp conditions.

How often should I water Brussels sprouts during the main growing phase (around head/bud formation)?

From transplanting through the period when the Brussels sprouts begin forming, keep soil evenly moist but not waterlogged—aim for about 1–1.5 inches (2.5–4 cm) of water per week depending on rainfall. Water deeply so moisture reaches the root zone, then let the top 1 inch (2.5 cm) of soil dry slightly before watering again. Consistent moisture helps the buds fill uniformly; irregular watering can lead to loose, stressed buds.

How can I tell when long Island Improved Brussels sprouts are ready to harvest?

Harvest when the individual Brussels sprouts are firm and reach about 1 to 1.5 inches (2.5–4 cm) across, starting from the bottom buds first. Use 90 days as a guide to timing, but rely on size and firmness: sprouts should feel tight, not soft or hollow. Stop when upper buds reach the same firmness/size, and harvest in cool weather for best texture.