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When to Plant Carrots in Payette County, ID

Payette County, Idaho Zone 7a May

What to do in May

Your garden in Payette County, Idaho is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost May 9
Avg. first frost October 1
Soil temp (4") 43°F
Watering High
Pest pressure Low
Daylight 14.6 hrs
Coming up in June — start thinking about
  • First harvests: carrots

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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.

Payette County, Idaho is in USDA Zone 7a. The average last spring frost is May 9 and the first fall frost is October 1, giving you a growing season of approximately 145 days.

At an elevation of 6,117 feet, Payette County receives approximately 24 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Carrots during the growing season.

Payette County, ID (Zone 7a) Short season
145 days
Last Spring Frost May 9
145 growing days
First Fall Frost October 1
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Payette County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (48 days to spare)
Transplant: May 1 🍅 Harvest: Jul 3 – Aug 7
Recommended (50%) ✓ Fits season (47 days to spare)
Transplant: May 9 🍅 Harvest: Jul 11 – Aug 15
Safe Start (90%) ✓ Fits season (38 days to spare)
Transplant: Jun 7 🍅 Harvest: Aug 9 – Sep 13

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 Payette County

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

Soil pH

Your soil pH (6.2–7.7) is more alkaline than Carrots prefers (6.0–6.8). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

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

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

2
successive plantings in your 145-day season

Sow every 6.9 weeks. Last sowing by Jul 13 to harvest before frost.

For a dedicated fall crop, sow by Jul 23.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.7″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 162 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — 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 1.5" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 1.8" 0" ❄️ Dormant
Apr 2.8" 0" ❄️ Dormant
May 3.5" 2.5" 1" 💧 Light watering
Jun 3.5" 1.8" 1.7" 💧 Light watering
Jul 3.5" 2.2" 1.3" 💧 Light watering
Aug 3.5" 2.7" 0.8" 💧 Light watering
Sep 3.5" 2.1" 1.4" 💧 Light watering
Oct 3.5" 2.2" 1.3" 💧 Light watering
Nov 1.7" 0" ❄️ Dormant
Dec 1.3" 0" ❄️ Dormant

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

Carrots needs ~1,225 GDD — county provides 2,537 GDD Excellent fit

Carrots Planting Timeline — Payette County, ID

Carrots Planting Calendar

Activity When Date Range
Direct Sow April 25 Apr 25 – May 16
Harvest June 27 Jun 27 – Aug 1
Fall Sowing July 23 Jul 23 – Aug 6

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Direct Sow
May Direct Sow
June Harvest
July Fall Sowing Harvest
August Fall Sowing Harvest
September
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Only during dry spells

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 6–6.8 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 7a

📆 Growing Season

145 days in Payette County

Growing Tips for Carrots in Payette County

Direct sow Carrots outdoors after May 09 in Payette 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 →

🌾 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 35°F, under 50% humidity.

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

Frequently Asked Questions

When should I plant Carrots in Payette County, ID?

Payette County is in Zone 7a with an average last frost of May 9. Plan your Carrots planting based on this frost date — see the calendar above for exact timing.

What planting zone is Payette County, ID?

Payette County, Idaho is in USDA Hardiness Zone 7a. The average last spring frost is May 9 and first fall frost is October 1.

🌱

Your Payette County Garden Planner — Free

A 24-page printable planner built for Payette County (Zone 7a). 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 Payette County, ID. 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.