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When to Plant Sorrel in Isabella County, MI

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.

Isabella County, Michigan is in USDA Zone 5a. The average last spring frost is May 4 and the first fall frost is October 13, giving you a growing season of approximately 162 days.

At an elevation of 1,136 feet, Isabella County receives approximately 35.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Sorrel to ensure they mature before fall.

Isabella County, MI (Zone 5a) Moderate season
162 days
Last Spring Frost May 4
162 growing days
First Fall Frost October 13

Isabella County Soil Profile

Soil Type

Silt Loam

Soil pH

6.3-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (61 days to spare)
Start indoors: Mar 24 Transplant: Apr 21 🍅 Harvest: Jun 2 – Aug 4
Recommended (50%) ✓ Fits season (64 days to spare)
Start indoors: Mar 30 Transplant: Apr 27 🍅 Harvest: Jun 8 – Aug 10
Safe Start (90%) ✓ Fits season (66 days to spare)
Start indoors: Apr 13 Transplant: May 11 🍅 Harvest: Jun 22 – Aug 24

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.

Soil Compatibility in Isabella County

How your county's soil matches Sorrel's growing requirements.

Soil pH

Your soil pH (6.3โ€“6.8) is within Sorrel's preferred range (5.5โ€“7.0).

Soil Texture

The silt loam soil in Isabella County is excellent for Sorrel โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.2%) โ€” Sorrel will thrive.

How to Plant Sorrel

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Sorrel

4
successive plantings in your 162-day season

Sow every 4.6 weeks. Last sowing by Aug 14 to harvest before frost.

For a dedicated fall crop, sow by Aug 04.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 126 gal / 100 sq ft

Monthly Watering Guide for Sorrel

Sorrel needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Sorrel Needs Rainfall You Supplement Action
Jan โ€” 1.6" 0" โ„๏ธ Dormant
Feb โ€” 1.4" 0" โ„๏ธ Dormant
Mar โ€” 2.6" 0" โ„๏ธ Dormant
Apr โ€” 3.4" 0" โ„๏ธ Dormant
May 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Jun 4.3" 4.4" 0" โœ… Rainfall sufficient
Jul 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
Aug 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Sep 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Oct 4.3" 2.7" 1.6" ๐Ÿ’ง Light watering
Nov โ€” 2.3" 0" โ„๏ธ Dormant
Dec โ€” 1.9" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Isabella County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Sorrel Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Sorrel needs ~650 GDD — county provides 2,106 GDD Excellent fit

Sorrel Planting Timeline โ€” Isabella County, MI

Sorrel Planting Calendar

Activity When Date Range
Start Indoors March 30 Mar 30 โ€“ Apr 13
Transplant Outdoors April 27 Apr 27 โ€“ May 11
Direct Sow April 20 Apr 20 โ€“ May 11
Harvest June 8 Jun 8 โ€“ Aug 10
Fall Sowing August 4 Aug 4 โ€“ Aug 18

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 Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June Harvest
July Harvest
August Fall Sowing Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

162 days in Isabella County

Growing Tips for Sorrel in Isabella County

Direct sow Sorrel outdoors after May 04 in Isabella County when soil has warmed and frost danger has passed.

Your generous 162.0-day season in Isabella County allows multiple plantings of Sorrel. Sow every 20.0 days for continuous harvest.

General growing tips

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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sorrel in Isabella County, MI?

Isabella County is in Zone 5a with an average last frost of May 4. Plan your Sorrel planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Isabella County, MI?

Isabella County, Michigan is in USDA Hardiness Zone 5a. The average last spring frost is May 4 and first fall frost is October 13.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Isabella County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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