When should I plant brassicas in Alaska?

In Alaska, brassicas is typically planted in fall between June 22 and July 7.

What USDA hardiness zone is Alaska?

Alaska has a dominant USDA hardiness zone of 4a, with a range from 1a to 7a. Last frost date averages around May 25 and first fall frost around September 5, giving a typical 105-day growing season.

What soil temperature does brassicas need to germinate?

Brassicas requires a minimum soil temperature of 45°F at 2-inch depth for reliable germination. Optimal germination occurs at 55–80°F.

State × crop calendar

Brassicas planting in Alaska.

Q: How long does brassicas take to mature?

Brassicas typically reaches maturity in 60–90 days, depending on variety. Late summer / early fall planting timing is critical for food plots — plants need 60-90 days of growth before first hard frost to reach peak forage value.

Primary crop
Zone 4a
105-day season
Last frost May 25
Cover Crop
Frost Hardy

Brassicas planting in Alaska is shaped by the state's 4a dominant hardiness zone, last frost date around May 25, and a 105-day growing season. Brassicas is widely grown in Alaska — commercially significant or common in home gardens and food plots.

Planting dates on this page are climatological estimates from USDA frost-date norms and zone-typical planting offsets. Verify against University of Alaska Cooperative Extension Service for variety- and county-specific guidance.

Planting calendar — 2026

Frost-anchored windows.

Brassicas · Alaska · planting calendar

Ideal windowEarliest / latest tailsFrost zone

Planting windows shift earlier in southern parts of the state and later in northern parts. Use last frost date in your specific county as the reference.

Planting windows

Earliest → ideal → latest.

Fall planting

Brassicas

Earliest

June 7

Ideal start

June 22

Ideal end

July 7

Latest

July 22

Soil-temp trigger

Late summer planting for fall food plot — 60-90 days before first hard frost provides peak forage value before deer season.

Harvest window

Typical start

August 21

Typical end

September 20

Harvest timing varies with planting date and seasonal weather — these dates are typical for the ideal planting window.

Growing notes

Brassicas grows well in Alaska's typical climate. Alaska's 105-day growing season and 4a hardiness zone support reliable production with appropriate variety selection.

Brassicas is widely grown in Alaska — commercially significant or common in home gardens and food plots.

Agronomy reference

Brassicas fundamentals.

Soil-temp minimum

45°F

Soil-temp optimum

55–80°F

Days to maturity

60–90

Water (in/wk)

0.5–1"

Soil pH

6–7.5

Nitrogen demand

moderate

Late summer / early fall planting timing is critical for food plots — plants need 60-90 days of growth before first hard frost to reach peak forage value.

Common pests to watch

Diamondback moth
Cabbage worms
Flea beetles

Pest pressure varies by region and year. Confirm current outbreaks with University of Alaska Cooperative Extension Service.

Common diseases

Black rot
Clubroot
Alternaria leaf spot

Resistance varieties shift each year. Check the current variety trial report for your state.

Variety selection

Brassicas varieties for Alaska live with your extension.

Variety selection

Variety performance is micro-regional and changes with each year's trial cycle. We don't republish variety lists — instead, we point directly at the source.

University of Alaska Cooperative Extension Service →

Search the extension site for “brassicas variety trial” or “recommended brassicas varieties” to find the current report.

Yield varies significantly by variety, soil, fertility, and management. Consult your state extension service for variety performance trials in your region.

Brassicas timing. Live alerts.

Bield: Farm ties weather and soil-temperature stations in your county to crop planting thresholds — get notified the day soil temp clears your target window.

Start free trial →

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