Soybean illustration

Growing Soybean in Zone 4b

Zone 4b has cold winters and a moderate growing season. Timing is key for Soybean in this zone. Last frost: May 1. First frost: Oct 5.

Planting Calendar

Outdoor
Harvest
May 8Oct 5

Season: May 1 – Oct 5 (157 days)

Zone4b
Last FrostMay 1
First FrostOct 5
Season Length157 days
Days to Harvest110
SunFull Sun
Frost ToleranceNone
Spacing4/sqft (6" apart)

When to Plant Soybean in Zone 4b

Sow Seeds Outdoors: May 8

Direct sow Soybean seeds outdoors around May 8. Soil temperature should be at least 60°F. Space at 4/sqft (6" apart).

Harvest: Aug 26

First harvest approximately Aug 26 (~110 days from planting). Continue harvesting until first frost (Oct 5).

Companion Planting

❌ Onion❌ Garlic

Frequently Asked Questions

When should I plant Soybean in Zone 4b?

Direct sow Soybean outdoors around May 8. Harvest around Aug 26.

What is the last frost date for Zone 4b?

The average last spring frost date for Zone 4b is May 1. The first fall frost averages Oct 5, giving a 157-day growing season.

Can I grow Soybean in Zone 4b?

Yes. Soybean needs 110 days to harvest. Zone 4b has a 157-day growing season, which is sufficient.

What is the best month to plant Soybean in Zone 4b?

The best time to plant Soybean in Zone 4b is around May 8, when soil temperatures are suitable and frost risk has passed.

What companion plants grow well with Soybean?

Good companion plants for Soybean include Corn, Squash, Sesame. Avoid planting Soybean near Onion, Garlic.

How long does Soybean take to harvest?

Soybean takes approximately 110 days from planting to harvest. In Zone 4b, expect your first harvest around Aug 26.

Plan Your Soybean Garden

Track Soybean from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

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