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When to Plant Sorrel in Clayton County, IA

Clayton County, Iowa Zone 5a April

This month in Clayton County, Iowa

A quick April briefing for Clayton County, Iowa gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 30
Avg. first frost October 7
Soil temp (4") 40°F
Watering Moderate
Pest pressure Low
Daylight 13.2 hrs
  1. Move sorrel into the garden

    Your last frost (April 30) has passed. These warm-season crops can handle outdoor soil now.

  2. Scatter sorrel into prepared beds

    Mark the row. Birds and stray feet both have opinions about unmarked beds.

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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.

Clayton County, Iowa is in USDA Zone 5a. The average last spring frost is April 30 and the first fall frost is October 7, giving you a growing season of approximately 160 days.

At an elevation of 1,343 feet, Clayton County receives approximately 32.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Sorrel to ensure they mature before fall.

Clayton County, IA (Zone 5a) Moderate season
160 days
Last Spring Frost April 30
160 growing days
First Fall Frost October 7

Clayton County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (61 days to spare)
Start indoors: Mar 20 Transplant: Apr 17 🍅 Harvest: May 29 – Jul 31
Recommended (50%) ✓ Fits season (62 days to spare)
Start indoors: Mar 26 Transplant: Apr 23 🍅 Harvest: Jun 4 – Aug 6
Safe Start (90%) ✓ Fits season (56 days to spare)
Start indoors: Apr 11 Transplant: May 9 🍅 Harvest: Jun 20 – Aug 22

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 Clayton County

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

Soil pH

Your soil pH (5.9–7.3) overlaps with Sorrel's range (5.5–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Clayton County is excellent for Sorrel — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (4.0%). Annual compost additions will help Sorrel.

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 160-day season

Sow every 4.6 weeks. Last sowing by Aug 08 to harvest before frost.

For a dedicated fall crop, sow by Jul 29.

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 198 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 1.3" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3" 1.3" 💧 Light watering
May 4.3" 3.2" 1.1" 💧 Light watering
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 2.8" 1.5" 💧 Light watering
Oct 4.3" 2.6" 1.7" 💧 Light watering
Nov 2.2" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Clayton County). Supplement amounts are based on average rainfall — 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" — every day above 50°F 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 ~538 GDD — county provides 1,720 GDD Excellent fit

Sorrel Planting Timeline — Clayton County, IA

Sorrel Planting Calendar

Activity When Date Range
Start Indoors March 26 Mar 26 – Apr 9
Transplant Outdoors April 23 Apr 23 – May 7
Direct Sow April 16 Apr 16 – May 7
Harvest June 4 Jun 4 – Aug 6
Fall Sowing July 29 Jul 29 – Aug 12

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 5.5–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

160 days in Clayton County

Growing Tips for Sorrel in Clayton County

Direct sow Sorrel outdoors after April 30 in Clayton County when soil has warmed and frost danger has passed.

Your generous 160.0-day season in Clayton 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 Clayton County, IA?

Clayton County is in Zone 5a with an average last frost of April 30. Plan your Sorrel planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clayton County, IA?

Clayton County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 30 and first fall frost is October 7.

🌱

Your Clayton County Garden Planner — Free

A 24-page printable planner built for Clayton County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.