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When to Plant Peppers in Franklin County, ID

Franklin County, Idaho Zone 6a May

Your May gardening checklist

Your Franklin County, Idaho garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.

Avg. last frost May 19
Avg. first frost October 3
Soil temp (4") 34°F
Watering High
Pest pressure Low
Daylight 14.4 hrs
  1. Put peppers seeds straight in the ground

    Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.

Coming up in June — start thinking about
  • Transplants going out: peppers

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Sweet peppers are warm-season crops producing fruits in a rainbow of colors. They turn from green to red, yellow, or orange as they ripen, increasing in sweetness.

Franklin County, Idaho is in USDA Zone 6a. The average last spring frost is May 19 and the first fall frost is October 3, giving you a growing season of approximately 137 days.

At an elevation of 7,665 feet, Franklin County receives approximately 18.5 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Peppers during the growing season. With low rainfall, drip irrigation is essential for growing Peppers successfully. Mulch heavily to conserve soil moisture.

Franklin County, ID (Zone 6a) Short season
137 days
Last Spring Frost May 19
137 growing days
First Fall Frost October 3
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Franklin County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 25 Transplant: May 20 🍅 Harvest: Jul 22 – Sep 30
Recommended (50%) ✗ May not fit
Start indoors: Mar 10 Transplant: Jun 2 🍅 Harvest: Aug 4 – Oct 13
Safe Start (90%) ✗ May not fit
Start indoors: Apr 4 Transplant: Jun 27 🍅 Harvest: Aug 29 – Nov 7

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 Franklin County

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

Soil pH

Your soil pH (6.7–7.7) is more alkaline than Peppers prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Peppers.

How to Plant Peppers

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Succession Planting Peppers

2
successive plantings in your 137-day season

Sow every 6.9 weeks. Last sowing by Jul 05 to harvest before frost.

Plant Water Budget

Plant needs
1.1″/week
Rainfall provides
0.6″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 780 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Peppers

Peppers needs approximately 1.1 inches of water per week (4.8" per month). Here's how your county's rainfall compares month by month.

Month Peppers Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1.1" 0" ❄️ Dormant
Mar 1.5" 0" ❄️ Dormant
Apr 2" 0" ❄️ Dormant
May 4.8" 1.9" 2.9" 🚿 Regular watering
Jun 4.8" 1.3" 3.5" 🚿 Regular watering
Jul 4.8" 1.8" 3" 🚿 Regular watering
Aug 4.8" 2" 2.8" 🚿 Regular watering
Sep 4.8" 1.6" 3.2" 🚿 Regular watering
Oct 4.8" 1.8" 3" 🚿 Regular watering
Nov 1.2" 0" ❄️ Dormant
Dec 1.1" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Franklin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Peppers 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.

Peppers needs ~1,144 GDD — county provides 2,089 GDD Excellent fit

Peppers Planting Timeline — Franklin County, ID

Peppers Planting Calendar

Activity When Date Range
Start Indoors March 10 Mar 10 – Mar 24
Transplant Outdoors June 2 Jun 2 – Jun 16
Direct Sow May 26 May 26 – Jun 16
Harvest August 4 Aug 4 – Oct 13

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.1"/week · 1-2 times/week

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 6a

📆 Growing Season

137 days in Franklin County

Growing Tips for Peppers in Franklin County

Direct sow Peppers outdoors after May 19 in Franklin County when soil has warmed and frost danger has passed.

Common pests for Peppers in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

Franklin County receives only 18" of rain annually. Peppers needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 8-10 weeks before last frost. Transplant when nighttime temperatures stay above 55F. Avoid high-nitrogen fertilizers which promote leaves over fruit.

Recommended Peppers Varieties for Franklin County

Fast-maturing pepper varieties for shorter seasons

Ace (50d) Gypsy (58d) Early Jalapeño (60d)

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel
  • Kohlrabi

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Peppers Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Remove seeds from fully ripe (red/orange) fruit.
Storage Store airtight; viable 4 years at 35°F, under 50% humidity.

Isolate 300 ft for purity. Hot and sweet peppers can cross-pollinate.

Frequently Asked Questions

When should I plant Peppers in Franklin County, ID?

Franklin County is in Zone 6a with an average last frost of May 19. Plan your Peppers planting based on this frost date — see the calendar above for exact timing.

What planting zone is Franklin County, ID?

Franklin County, Idaho is in USDA Hardiness Zone 6a. The average last spring frost is May 19 and first fall frost is October 3.

🌱

Your Franklin County Garden Planner — Free

A 24-page printable planner built for Franklin County (Zone 6a). 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 Franklin 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.