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When to Plant Kohlrabi in Simms, Montana (59477)

Location

Simms, Montana

ZIP Code

59477

USDA Zone

4b

Last Frost

Tuesday, May 5, 2026

📅 Planting Calendar

Start Seeds Indoors Tuesday, April 7, 2026
Transplant Outdoors Tuesday, April 21, 2026

Pro Tip: Start Kohlrabi seeds indoors 4 weeks before your last frost date, then transplant outdoors around Tuesday, April 21, 2026.

🌿 Plant Details

Scientific Name Brassica oleracea var. gongylodes
Days to Maturity 55 days
Mature Height 12-18"
Spread 8"
Type Bulb
Fruit Size Small-Medium (2-3 inch bulb)

☀️ Growing Requirements

☀️

Sun

Full Sun to Partial Shade

💧

Water

Regular (consistent moisture prevents cracking)

↔️

Spacing

6" apart

🌱

Planting Depth

0.5" deep

Seeds typically germinate in 4-7 days

Ready to Plant Kohlrabi in Simms?

Get your seeds now so they're ready by Tuesday, April 7, 2026.

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🤝 Good Companions

BeetOnionCucumberHerb

⚠️ Avoid Planting Near

TomatoPepperStrawberry

Other Plants for Simms

Growing Kohlrabi in Zone 4b

Kohlrabi (Brassica oleracea var. gongylodes) is a popular garden vegetable. In Simms, Montana, which is in USDA Hardiness Zone 4b, you should start seeds indoors around Tuesday, April 7, 2026.

Your average last frost date is Tuesday, May 5, 2026. Plan to transplant your Kohlrabi seedlings outdoors around Tuesday, April 21, 2026, about -2 weeks after your last frost date.