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When to Plant Sorrel in Madison County, IA

Madison County, Iowa Zone 5b May

This month in Madison County, Iowa

We've pulled the most time-sensitive tasks for Madison County, Iowa this May and put them front and centre. Tackle them in order.

Avg. last frost April 24
Avg. first frost October 11
Soil temp (4") 60°F
Watering Low
Pest pressure Low
Daylight 14.3 hrs
  1. Begin indoor sowing: sorrel

    Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.

  2. Bring in the sorrel

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

A few tasks this May that'll pay off in June
  • First harvests: sorrel

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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.

Madison County, Iowa is in USDA Zone 5b. The average last spring frost is April 24 and the first fall frost is October 11, giving you a growing season of approximately 170 days.

At an elevation of 1,022 feet, Madison County receives approximately 40.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Sorrel to ensure they mature before fall.

Madison County, IA (Zone 5b) Moderate season
170 days
Last Spring Frost April 24
170 growing days
First Fall Frost October 11

Madison County Soil Profile

Soil Type

Silt Loam

Soil pH

6.3-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (72 days to spare)
Start indoors: Mar 14 Transplant: Apr 11 🍅 Harvest: May 23 – Jul 25
Recommended (50%) ✓ Fits season (72 days to spare)
Start indoors: Mar 20 Transplant: Apr 17 🍅 Harvest: May 29 – Jul 31
Safe Start (90%) ✓ Fits season (70 days to spare)
Start indoors: Apr 4 Transplant: May 2 🍅 Harvest: Jun 13 – Aug 15

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 Madison County

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

Soil pH

Your soil pH (6.3–6.9) is within Sorrel's preferred range (5.5–7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.3%) — 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

5
successive plantings in your 170-day season

Sow every 4.6 weeks. Last sowing by Aug 12 to harvest before frost.

For a dedicated fall crop, sow by Aug 02.

Plant Water Budget

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

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.9" 0" ❄️ Dormant
Feb 2" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.3" 4" 0.3" 💧 Light watering
May 4.3" 5.4" 0" ✅ Rainfall sufficient
Jun 4.3" 5" 0" ✅ Rainfall sufficient
Jul 4.3" 4" 0.3" 💧 Light watering
Aug 4.3" 3.7" 0.6" 💧 Light watering
Sep 4.3" 3.8" 0.5" 💧 Light watering
Oct 4.3" 3.4" 0.9" 💧 Light watering
Nov 2.4" 0" ❄️ Dormant
Dec 2.4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Madison 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 ~650 GDD — county provides 2,210 GDD Excellent fit

Sorrel Planting Timeline — Madison County, IA

Sorrel Planting Calendar

Activity When Date Range
Start Indoors March 20 Mar 20 – Apr 3
Transplant Outdoors April 17 Apr 17 – May 1
Direct Sow April 10 Apr 10 – May 1
Harvest May 29 May 29 – Jul 31
Fall Sowing August 2 Aug 2 – Aug 16

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 Harvest
June Harvest
July Harvest
August Fall Sowing
September
October
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 5.5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 5b

📆 Growing Season

170 days in Madison County

Growing Tips for Sorrel in Madison County

Direct sow Sorrel outdoors after April 24 in Madison County when soil has warmed and frost danger has passed.

Your generous 170.0-day season in Madison 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 Madison County, IA?

Madison County is in Zone 5b with an average last frost of April 24. Plan your Sorrel planting based on this frost date — see the calendar above for exact timing.

What planting zone is Madison County, IA?

Madison County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 24 and first fall frost is October 11.

🌱

Your Madison County Garden Planner — Free

A 24-page printable planner built for Madison County (Zone 5b). 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 Madison County, IA. Local conditions may vary. Last updated: May 2026.

Sources & credits

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