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When to Plant Sweet Alyssum in Simms, Montana (59477)

Location

Simms, Montana

ZIP Code

59477

USDA Zone

4b

Last Frost

Tuesday, May 5, 2026

๐Ÿ“… Planting Calendar

Direct Sow Outdoors Tuesday, April 7, 2026

Pro Tip: Sow Sweet Alyssum directly outdoors 4 weeks before your last frost date.

๐ŸŒฟ Plant Details

Scientific Name Lobularia maritima
Days to Maturity 45 days
Mature Height 4-8"
Spread 9"

โ˜€๏ธ Growing Requirements

โ˜€๏ธ

Sun

Full Sun to Partial Shade

๐Ÿ’ง

Water

Moderate (1 inch/week)

โ†”๏ธ

Spacing

6" apart

๐ŸŒฑ

Planting Depth

0.125" deep

Seeds typically germinate in 5-10 days

Ready to Plant Sweet Alyssum in Simms?

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

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๐Ÿค Good Companions

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Growing Sweet Alyssum in Zone 4b

Sweet Alyssum (Lobularia maritima) is a popular garden vegetable. In Simms, Montana, which is in USDA Hardiness Zone 4b, you should direct sow seeds around Tuesday, April 7, 2026.

Your average last frost date is Tuesday, May 5, 2026. Sweet Alyssum grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.