When to Plant Sunflower in Biwabik, Minnesota (55708)
Location
Biwabik, Minnesota
ZIP Code
55708
USDA Zone
3b
Last Frost
Wednesday, May 20, 2026
๐ Planting Calendar
Pro Tip: Sow Sunflower directly outdoors 1 week after your last frost date โ it needs warm soil.
๐ฟ Plant Details
โ๏ธ Growing Requirements
โ๏ธ
Sun
Full Sun (6-8 hours)
๐ง
Water
Low-Moderate (1 inch/week)
โ๏ธ
Spacing
18" apart
๐ฑ
Planting Depth
1" deep
Seeds typically germinate in 7-14 days
Ready to Plant Sunflower in Biwabik?
Get your seeds now so they're ready by Wednesday, May 27, 2026.
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๐ค Good Companions
โ ๏ธ Avoid Planting Near
Other Plants for Biwabik
Growing Sunflower in Zone 3b
Sunflower (Helianthus annuus) is a popular garden vegetable. In Biwabik, Minnesota, which is in USDA Hardiness Zone 3b, you should direct sow seeds around Wednesday, May 27, 2026.
Your average last frost date is Wednesday, May 20, 2026. Sunflower grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.