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When to Plant Carrots in Johnson County, KS

Carrots are a popular root vegetable available in orange, purple, white, and yellow varieties. They are rich in beta-carotene and have a sweet, earthy flavor.

Johnson County, Kansas is in USDA Zone 6a. The average last spring frost is April 8 and the first fall frost is October 26, giving you a growing season of approximately 201 days.

At an elevation of 768 feet, Johnson County receives approximately 27.6 inches of rainfall annually with predominantly loam soil. Summer highs average 87ยฐF, providing good warmth for Carrots during the growing season.

Johnson County, KS (Zone 6a) Long season
201 days
Last Spring Frost April 8
201 growing days
First Fall Frost October 26

Johnson County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (103 days to spare)
Transplant: Apr 4 🍅 Harvest: Jun 6 – Jul 11
Recommended (50%) ✓ Fits season (103 days to spare)
Transplant: Apr 8 🍅 Harvest: Jun 10 – Jul 15
Safe Start (90%) ✓ Fits season (107 days to spare)
Transplant: Apr 23 🍅 Harvest: Jun 25 – 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 Johnson County

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

Soil pH

Your soil pH (6.8โ€“7.2) is more alkaline than Carrots prefers (6.0โ€“6.8). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.2%) โ€” Carrots will thrive.

How to Plant Carrots

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Carrots

3
successive plantings in your 201-day season

Sow every 6.9 weeks. Last sowing by Aug 07 to harvest before frost.

For a dedicated fall crop, sow by Aug 17.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.6″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 479 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Carrots

Carrots needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Carrots Needs Rainfall You Supplement Action
Jan โ€” 0.8" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar โ€” 1.9" 0" โ„๏ธ Dormant
Apr 3.5" 3.2" 0.3" ๐Ÿ’ง Light watering
May 3.5" 3.7" 0" โœ… Rainfall sufficient
Jun 3.5" 4.1" 0" โœ… Rainfall sufficient
Jul 3.5" 3.8" 0" โœ… Rainfall sufficient
Aug 3.5" 3.5" 0" โœ… Rainfall sufficient
Sep 3.5" 2.3" 1.2" ๐Ÿ’ง Light watering
Oct 3.5" 1.8" 1.7" ๐Ÿ’ง Light watering
Nov โ€” 1" 0" โ„๏ธ Dormant
Dec โ€” 0.7" 0" โ„๏ธ Dormant

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

Carrots 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.

Carrots needs ~1,068 GDD — county provides 3,065 GDD Excellent fit

Carrots Planting Timeline โ€” Johnson County, KS

Carrots Planting Calendar

Activity When Date Range
Direct Sow March 25 Mar 25 โ€“ Apr 15
Harvest May 27 May 27 โ€“ Jul 1
Fall Sowing August 17 Aug 17 โ€“ Aug 31

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.8"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

60โ€“80 days

๐Ÿงช Soil pH

Needs 6โ€“6.8 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

201 days in Johnson County

Growing Tips for Carrots in Johnson County

Direct sow Carrots outdoors after April 08 in Johnson County when soil has warmed and frost danger has passed.

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

General growing tips

Sow seeds directly in loose, stone-free soil for straight roots. Keep soil moist until germination which can take 2-3 weeks. Thin seedlings to 2 inches apart.

Companion Planting

Good Companions

Avoid Planting Near

  • Dill
  • Parsnip

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Carrots Seeds
Life Cycle Biennial
Pollination Cross-Pollinated (insects)
How to Collect Replant roots for 2nd year flowers. Harvest umbels when brown.
Storage Store airtight; viable 3 years at 35ยฐF, under 50% humidity.

Isolate 1/2 mile from Queen Anne's Lace (wild carrot). Biennial โ€” requires two seasons.

Frequently Asked Questions

When should I plant Carrots in Johnson County, KS?

Johnson County is in Zone 6a with an average last frost of April 8. Plan your Carrots planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Johnson County, KS?

Johnson County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 8 and first fall frost is October 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Johnson County gardeners in Zone 6a 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 Johnson County, KS. Local conditions may vary. Last updated: April 2026.