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When to plant Chervil in Jackson County, CO

In Zone 4b (Jackson County), direct-sow Chervil between June 6 and June 27 for spring, after the June 13 last-frost mark. A second sowing from June 12 to June 26 extends the harvest into fall.

When to Plant Chervil in Jackson County, CO

Jackson County, Colorado Zone 4b June

What to do in June

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost June 13
Avg. first frost September 4
Soil temp (4") 49°F
Watering High
Pest pressure Moderate
Daylight 14.9 hrs
  1. Harden off and plant chervil

    Water the tray well an hour before you transplant. Roots slide out cleanly and settle in faster.

  2. Sow chervil where they'll grow

    Succession planting is the secret here. Put in a row now, another in 2 weeks, a third in 4.

  3. Start your fall crops: chervil

    Count back from your first frost (September 4) — these need to mature before the cold arrives.

Coming up in July — start thinking about
  • Starting indoors: chervil
  • First harvests: chervil

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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.

Jackson County, Colorado is in USDA Zone 4b. The average last spring frost is June 13 and the first fall frost is September 4, giving you a growing season of approximately 83 days.

At an elevation of 5,388 feet, Jackson County receives approximately 20.9 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Chervil to ensure they mature before fall.

Jackson County, CO (Zone 4b) Very short season
83 days
Last Spring Frost June 13
83 growing days
First Fall Frost September 4

Jackson County Soil Profile

Soil Type

Loam

Soil pH

6.6-8.1

Drainage

Well Drained

Chervil Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 27 Transplant: Jun 1 🍅 Harvest: Jul 13 – Sep 14
Recommended (50%) ✗ May not fit
Start indoors: May 2 Transplant: Jun 6 🍅 Harvest: Jul 18 – Sep 19
Safe Start (90%) ✗ May not fit
Start indoors: May 14 Transplant: Jun 18 🍅 Harvest: Jul 30 – Oct 1

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 Jackson County

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

Soil pH

Your soil pH (6.6–8.1) is more alkaline than Chervil prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Chervil.

How to Plant Chervil

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

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Chervil

2
successive plantings in your 83-day season

Sow every 4.6 weeks. Last sowing by Jul 06 to harvest before frost.

For a dedicated fall crop, sow by Jun 12.

Chervil Water Budget

Plant needs
0.5″/week
Rainfall provides
1.1″/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 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 1.6" 0" ❄️ Dormant
Feb 1.1" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 2.3" 0" ❄️ Dormant
May 2.2" 0" ❄️ Dormant
Jun 2.2" 1.7" 0.5" 💧 Light watering
Jul 2.2" 1.7" 0.5" 💧 Light watering
Aug 2.2" 2.5" 0" ✅ Rainfall sufficient
Sep 2.2" 1.5" 0.7" 💧 Light watering
Oct 2.1" 0" ❄️ Dormant
Nov 1.4" 0" ❄️ Dormant
Dec 1.1" 0" ❄️ Dormant

Water needs are for active growing months only (Jun–Sep in Jackson 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 ~500 GDD — county provides 830 GDD Excellent fit

Chervil Planting Timeline — Jackson County, CO

Chervil Planting Calendar

Activity When Date Range
Start Indoors May 2 May 2 – May 16
Transplant Outdoors June 6 Jun 6 – Jun 20
Direct Sow June 6 Jun 6 – Jun 27
Harvest July 18 Jul 18 – Sep 19
Fall Sowing June 12 Jun 12 – Jun 26

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

Month-by-Month Timeline

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

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: too_alkaline

🗺️ USDA Zone

Zone 4b

📆 Growing Season

83 days in Jackson County

Growing Tips for Chervil in Jackson County

Direct sow Chervil outdoors after June 13 in Jackson County when soil has warmed and frost danger has passed.

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 Jackson County, CO?

Jackson County is in Zone 4b with an average last frost of June 13. Plan your Chervil planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jackson County, CO?

Jackson County, Colorado is in USDA Hardiness Zone 4b. The average last spring frost is June 13 and first fall frost is September 4.

When should I plant Chervil in Jackson County, CO?

In Jackson County, CO, plant Chervil after the last frost (around June 13) and before the first frost (around September 4). Best results when soil holds above 50°F.

What growing zone is Jackson County, CO for Chervil?

Jackson County sits in USDA Zone 4b. Chervil grows reliably in zones 3a through 10b, so it's a good fit here.

Can Chervil grow in Jackson County's climate?

Yes — Chervil grows well in Jackson County's temperate climate. Jackson County averages a 83-day frost-free season, with last frost around June 13 and first frost around September 4.

🌱

Your Jackson County Garden Planner — Free

A 22-page printable planner built for Jackson County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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

Sources & credits

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