When to Plant Brussels Sprouts in Zone 3

Brassica oleracea var. gemmifera

Last updated: Apr 29, 2026 · Sources: USDA, NOAA, Cooperative Extension
Action Plan

Plant Brussels Sprouts in Zone 3

  • Start indoors: Mar 27
  • Transplant: May 15 — after last frost (May 15)
  • First harvest: Aug 10 (80–110 days after planting)
⚠️ Don't plant before last frost (May 15) — cold snaps kill young transplants.
Last frost
May 15
First frost
Sep 15
Growing season
123 days
Quick Facts
Sunlight ☀️ Full Sun
Water Needs 💧💧 Moderate
Spacing 24 inches apart
Planting Depth 0.5 inch
Min Soil Temp 40°F
Germination 5–10 days
Days to Maturity 80–110 days
Frost Tolerance Heavy frost tolerance
Soil pH 6.0–7.5
Difficulty Moderate
What you'll need — Zone 3
🛒 Brussels Sprouts — Seeds & Supplies
  • 🌱 Brussels Sprouts Seeds
  • 🌱 Row Cover for Frost Extension
  • 🌱 Garden Calendar Planner

Search for these at your local garden center or nursery.

Growing Tips

  • Brussels sprouts need the longest growing season of any vegetable — up to 110 days.
  • Start indoors 12–14 weeks before first fall frost — they're best as a fall crop.
  • Remove lower leaves as sprouts develop from the bottom up.
  • Frost dramatically improves flavor — leave them in the ground as long as possible.
  • Snap off the top growing tip 4 weeks before harvest to encourage final sprout size.

Common Mistakes

  • Planting as a spring crop — usually fails due to summer heat.
  • Not removing lower leaves — trapped moisture causes disease.
  • Harvesting too early — wait until after the first frost for best flavor.
  • Not topping the plant — the tip diverts energy away from sprout development.

Companion Planting

Companion planting improves growth, deters pests, and makes better use of garden space.

✓ Good Companions

Onion Celery

✗ Avoid Nearby

Tomato Strawberry

Brussels Sprouts Schedule — All Zones

ZoneStart IndoorsTransplant Direct SowHarvest StartHarvest End
Zone 3 Mar 27 May 15 — Aug 10 Sep 12
Zone 4 Mar 22 May 10 — Aug 5 Sep 22
Zone 5 Mar 12 Apr 30 — Jul 26 Sep 24
Zone 6 Feb 25 Apr 15 — Jul 11 Sep 9
Zone 7 Feb 15 Apr 5 — Jul 1 Aug 30
Zone 8 Jan 30 Mar 20 — Jun 15 Aug 14
Zone 9 Jan 10 Feb 28 — May 26 Jul 25
Zone 10 Dec 23 Feb 10 — May 8 Jul 7

Other Zones for Brussels Sprouts

Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8 · Zone 9 · Zone 10

📚 Data Sources
Frost dates: NOAA Climate Normals 1991–2020, National Centers for Environmental Information.
Hardiness zones: USDA Plant Hardiness Zone Map, Agricultural Research Service.
Growing requirements: Cooperative Extension Services — NC State, Penn State, University of Florida IFAS.
Companion planting: Cornell University Cooperative Extension.
Data compiled from public agricultural sources. Always verify with your local extension office for micro-climate adjustments.