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When to Plant Sorrel in Oconto County, WI

Sorrel is a perennial herb with tangy, lemon-flavored arrow-shaped leaves. It is one of the first greens to emerge in spring and is used in soups and salads.

Oconto County, Wisconsin is in USDA Zone 4b. The average last spring frost is May 9 and the first fall frost is October 4, giving you a growing season of approximately 148 days.

At an elevation of 794 feet, Oconto County receives approximately 37.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80ยฐF, so choose short-season varieties of Sorrel to ensure they mature before fall.

Oconto County, WI (Zone 4b) Short season
148 days
Last Spring Frost May 9
148 growing days
First Fall Frost October 4

Oconto County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (51 days to spare)
Start indoors: Mar 22 Transplant: Apr 26 🍅 Harvest: Jun 7 – Aug 9
Recommended (50%) ✓ Fits season (50 days to spare)
Start indoors: Mar 28 Transplant: May 2 🍅 Harvest: Jun 13 – Aug 15
Safe Start (90%) ✓ Fits season (49 days to spare)
Start indoors: Apr 14 Transplant: May 19 🍅 Harvest: Jun 30 – Sep 1

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Sorrel needs ~500 GDD — county provides 1,480 GDD Excellent fit

Sorrel Planting Timeline โ€” Oconto County, WI

Sorrel Planting Calendar

Activity When Date Range
Start Indoors March 28 Mar 28 โ€“ Apr 11
Transplant Outdoors May 2 May 2 โ€“ May 16
Direct Sow May 2 May 2 โ€“ May 23
Fall Sowing July 12 Jul 12 โ€“ Jul 26
Harvest June 13 Jun 13 โ€“ Aug 15

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April Start Indoors
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

40โ€“60 days

Soil pH

5.5 โ€“ 7

USDA Zone

Zone 4b

Growing Season

148 days

Growing Tips for Oconto County

Direct sow in early spring or fall. Remove flower stalks promptly to encourage leaf production. Divide clumps every 3-4 years. Young leaves have the best flavor.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Sorrel in Oconto County, WI?

Oconto County is in Zone 4b with an average last frost of May 9. Plan your Sorrel planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Oconto County, WI?

Oconto County, Wisconsin is in USDA Hardiness Zone 4b. The average last spring frost is May 9 and first fall frost is October 4.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Oconto County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Oconto County, WI. Local conditions may vary. Last updated: April 2026.