Blog

When to Plant Chervil in Polk County, MO

Polk County, Missouri Zone 6b May

Your May planting checklist for Polk County, Missouri

May is a pivotal month for Polk County, Missouri gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 10
Avg. first frost October 22
Soil temp (4") 64°F
Watering Low
Pest pressure Low
Daylight 14 hrs
  1. Start chervil under lights

    These need a head start before your last frost (April 10). Sow into cells now so you're ready to transplant in a few weeks.

  2. Collect chervil at their peak

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

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

Instant PDF download. No spam, unsubscribe any time.

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.

Polk County, Missouri is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 22, giving you a growing season of approximately 195 days.

At an elevation of 1,363 feet, Polk County receives approximately 31.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Chervil during the growing season.

Polk County, MO (Zone 6b) Moderate season
195 days
Last Spring Frost April 10
195 growing days
First Fall Frost October 22
Share this guide:

Polk County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (97 days to spare)
Start indoors: Feb 28 Transplant: Mar 28 🍅 Harvest: May 9 – Jul 11
Recommended (50%) ✓ Fits season (97 days to spare)
Start indoors: Mar 6 Transplant: Apr 3 🍅 Harvest: May 15 – Jul 17
Safe Start (90%) ✓ Fits season (98 days to spare)
Start indoors: Mar 19 Transplant: Apr 16 🍅 Harvest: May 28 – Jul 30

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 Polk County

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

Soil pH

Your soil pH (5.4–6.9) overlaps with Chervil's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.1%). 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 195-day season

Sow every 4.6 weeks. Last sowing by Aug 23 to harvest before frost.

For a dedicated fall crop, sow by Aug 13.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.7″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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 1.3" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 2.2" 3" 0" ✅ Rainfall sufficient
May 2.2" 4.3" 0" ✅ Rainfall sufficient
Jun 2.2" 3.8" 0" ✅ Rainfall sufficient
Jul 2.2" 3.5" 0" ✅ Rainfall sufficient
Aug 2.2" 3.4" 0" ✅ Rainfall sufficient
Sep 2.2" 2.5" 0" ✅ Rainfall sufficient
Oct 2.2" 2.2" 0" ✅ Rainfall sufficient
Nov 1.9" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Polk County). Supplement amounts are based on average rainfall — 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" — 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.

Chervil needs ~800 GDD — county provides 3,120 GDD Excellent fit

Chervil Planting Timeline — Polk County, MO

Chervil Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 – Mar 20
Transplant Outdoors April 3 Apr 3 – Apr 17
Direct Sow March 27 Mar 27 – Apr 17
Harvest May 15 May 15 – Jul 17
Fall Sowing August 13 Aug 13 – Aug 27

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

195 days in Polk County

Growing Tips for Chervil in Polk County

Direct sow Chervil outdoors after April 10 in Polk County when soil has warmed and frost danger has passed.

Your generous 195.0-day season in Polk 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 Polk County, MO?

Polk County is in Zone 6b with an average last frost of April 10. Plan your Chervil planting based on this frost date — see the calendar above for exact timing.

What planting zone is Polk County, MO?

Polk County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 22.

🌱

Your Polk County Garden Planner — Free

A 24-page printable planner built for Polk County (Zone 6b). 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 Polk County, MO. 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.