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When to Plant Chervil in Cedar County, IA

Chervil is a delicate herb with a subtle anise-parsley flavor, essential in French cuisine as part of fines herbes. It prefers cool conditions and partial shade.

Cedar County, Iowa is in USDA Zone 5a. The average last spring frost is April 17 and the first fall frost is October 16, giving you a growing season of approximately 182 days.

At an elevation of 1,112 feet, Cedar County receives approximately 41 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87ยฐF, providing good warmth for Chervil during the growing season.

Cedar County, IA (Zone 5a) Moderate season
182 days
Last Spring Frost April 17
182 growing days
First Fall Frost October 16

Cedar County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (82 days to spare)
Start indoors: Mar 8 Transplant: Apr 5 🍅 Harvest: May 17 – Jul 19
Recommended (50%) ✓ Fits season (84 days to spare)
Start indoors: Mar 13 Transplant: Apr 10 🍅 Harvest: May 22 – Jul 24
Safe Start (90%) ✓ Fits season (80 days to spare)
Start indoors: Apr 3 Transplant: May 1 🍅 Harvest: Jun 12 – Aug 14

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 Cedar County

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

Soil pH

Your soil pH (5.9โ€“6.9) overlaps with Chervil's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Chervil.

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Chervil.

How to Plant Chervil

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 Chervil

5
successive plantings in your 182-day season

Sow every 4.6 weeks. Last sowing by Aug 17 to harvest before frost.

For a dedicated fall crop, sow by Aug 07.

Plant Water Budget

Plant needs
0.5″/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 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Chervil

Chervil needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Chervil Needs Rainfall You Supplement Action
Jan โ€” 1.6" 0" โ„๏ธ Dormant
Feb โ€” 1.5" 0" โ„๏ธ Dormant
Mar โ€” 2.8" 0" โ„๏ธ Dormant
Apr 2.2" 3.4" 0" โœ… Rainfall sufficient
May 2.2" 5.1" 0" โœ… Rainfall sufficient
Jun 2.2" 5.3" 0" โœ… Rainfall sufficient
Jul 2.2" 4.9" 0" โœ… Rainfall sufficient
Aug 2.2" 4.7" 0" โœ… Rainfall sufficient
Sep 2.2" 3.5" 0" โœ… Rainfall sufficient
Oct 2.2" 3.2" 0" โœ… Rainfall sufficient
Nov โ€” 3" 0" โ„๏ธ Dormant
Dec โ€” 2" 0" โ„๏ธ Dormant

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

Chervil 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.

Chervil needs ~762 GDD — county provides 2,775 GDD Excellent fit

Chervil Planting Timeline โ€” Cedar County, IA

Chervil Planting Calendar

Activity When Date Range
Start Indoors March 13 Mar 13 โ€“ Mar 27
Transplant Outdoors April 10 Apr 10 โ€“ Apr 24
Direct Sow April 3 Apr 3 โ€“ Apr 24
Harvest May 22 May 22 โ€“ Jul 24
Fall Sowing August 7 Aug 7 โ€“ Aug 21

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

182 days in Cedar County

Growing Tips for Chervil in Cedar County

Direct sow Chervil outdoors after April 17 in Cedar County when soil has warmed and frost danger has passed.

Your generous 182.0-day season in Cedar County allows multiple plantings of Chervil. Sow every 20.0 days for continuous harvest.

Common pests for Chervil in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in early spring or fall as chervil bolts in heat. Provide shade and cool conditions. Harvest outer leaves as needed; use fresh as it loses flavor when dried.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Chervil in Cedar County, IA?

Cedar County is in Zone 5a with an average last frost of April 17. Plan your Chervil planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Cedar County, IA?

Cedar County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 17 and first fall frost is October 16.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Cedar 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 Cedar County, IA. Local conditions may vary. Last updated: April 2026.