đąWhen to Plant Peas in USDA Zone 4a (2026 Guide)
Sow as soon as soil can be worked â peas love the cold. Here is the cool-season planting schedule for peas in zone 4a (covering areas like northern Wisconsin, Fargo ND). All dates are based on 2026 frost data for your zone.
Direct sow
Mar 29
Harvest From
May 28
Because peas is a cool-season crop, it tolerates light frost and can go out around Mar 29, before zone 4a's average last frost on May 10.
- Type: Cool-season
- Method: Direct sow
- Days to harvest: 60
- Spacing: 2" apart
- Sun: Full sun to part shade
- Zone 4a frost: May 10 â Sep 25
- Season length: ~138 days
- Companions: carrot, radish, cucumber
Growing peas in zone 4a
Zone 4a has an average last spring frost around May 10 and a first fall frost around Sep 25, giving roughly 138 frost-free growing days. That window comfortably fits peas's 60-day cycle, with room for a second succession planting if you time it right.
Peas resents transplanting, so direct sow it right in the garden around Mar 29. Give each plant about 2 inches of space in full sun to part shade.
Zone 4a specific growing notes
In zone 4a (northern Wisconsin, Fargo ND), your 138-day growing season means peas should be one of your first spring plantings. Cool-season crops thrive in the mild part of your growing window. Monitor soil temperature â peas germinates best when soil is 40-75°F.
Your first fall frost around Sep 25 means your last possible harvest is roughly late Sep. For a continuous supply, consider succession planting every 2-3 weeks from Mar 29 through mid-season.
Pro tip for peas
Install trellis or netting at planting time, not afterâpeas send out tendrils immediately and tangled vines break when you try to untangle them. Soak seeds overnight before planting for faster germination in cold soil.
Troubleshooting peas
Powdery mildew (white powder on leaves) strikes late plantings as weather warms. The best defense is planting early so peas finish before hot weather arrives. Choose resistant varieties like 'Sugar Snap' for later sowings.
Growing peas in containers
Dwarf pea varieties in 8-inch deep containers with a small trellis thrive on patios. 'Tom Thumb' grows only 8-10 inches tall and needs no support at allâperfect for small containers.
Can you plant peas twice a year?
Yesâsow a fall crop in late July to early August in zones 5+. Peas love cooling autumn weather. Count back 60-70 days from your first fall frost date to time the planting.
Frequently asked questions
When should I plant peas in zone 4a?
Direct sow around Mar 29. Because peas is a cool-season crop, it tolerates light frost and can go out around Mar 29, before zone 4a's average last frost on May 10.
How long does peas take to grow in zone 4a?
About 60 days from sowing to first harvest. A Mar 29 planting in zone 4a is typically ready to pick from around May 28. Zone 4a has about 138 frost-free days â plenty of time for a second succession planting.
How far apart should I space peas?
Space peas about 2 inches apart in full sun to part shade. This gives each plant enough room for roots to spread and leaves to catch sunlight without competing.
What is the best tip for growing peas?
Install trellis or netting at planting time, not afterâpeas send out tendrils immediately and tangled vines break when you try to untangle them. Soak seeds overnight before planting for faster germination in cold soil.
What are common problems with peas and how do I fix them?
Powdery mildew (white powder on leaves) strikes late plantings as weather warms. The best defense is planting early so peas finish before hot weather arrives. Choose resistant varieties like 'Sugar Snap' for later sowings.
Can I grow peas in a container?
Dwarf pea varieties in 8-inch deep containers with a small trellis thrive on patios. 'Tom Thumb' grows only 8-10 inches tall and needs no support at allâperfect for small containers.
Can I plant a second crop of peas for fall harvest?
Yesâsow a fall crop in late July to early August in zones 5+. Peas love cooling autumn weather. Count back 60-70 days from your first fall frost date to time the planting.
What grows well next to peas?
Good companion plants for peas are carrot, radish, cucumber. Avoid planting near warm-season crops that compete for space and nutrients. Peas also benefits from crop rotation â do not plant it in the same spot year after year.