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When to Plant Hot Peppers in Boise County, ID

Boise County, Idaho Zone 7a May

Your May gardening checklist

We've pulled the most time-sensitive tasks for Boise County, Idaho this May and put them front and centre. Tackle them in order.

Avg. last frost May 18
Avg. first frost September 27
Soil temp (4") 34°F
Watering Moderate
Pest pressure Low
Daylight 14.6 hrs
  1. Direct-sow hot peppers

    These tolerate cool soil, so you're not gambling by sowing now.

June prep starts now
  • Transplants going out: hot peppers

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Hot peppers range from mildly spicy jalapenos to scorching superhots. They require long, warm growing seasons and produce capsaicin that gives them their heat.

Boise County, Idaho is in USDA Zone 7a. The average last spring frost is May 18 and the first fall frost is September 27, giving you a growing season of approximately 132 days.

At an elevation of 8,023 feet, Boise County receives approximately 24.3 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Hot Peppers during the growing season.

Boise County, ID (Zone 7a) Short season
132 days
Last Spring Frost May 18
132 growing days
First Fall Frost September 27

Boise 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: Mar 3 Transplant: May 19 🍅 Harvest: Jul 28 – Nov 3
Recommended (50%) ✗ May not fit
Start indoors: Mar 16 Transplant: Jun 1 🍅 Harvest: Aug 10 – Nov 16
Safe Start (90%) ✗ May not fit
Start indoors: Apr 14 Transplant: Jun 30 🍅 Harvest: Sep 8 – Dec 15

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 Boise County

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

Soil pH

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

Soil Texture

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

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Hot Peppers.

How to Plant Hot Peppers

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

Succession Planting Hot Peppers

2
successive plantings in your 132-day season

Sow every 8 weeks. Last sowing by May 30 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 320 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Hot Peppers

Hot Peppers needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Hot Peppers Needs Rainfall You Supplement Action
Jan 1.8" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 2.4" 0" ❄️ Dormant
May 4.3" 3" 1.3" 💧 Light watering
Jun 4.3" 1.9" 2.4" 🚿 Regular watering
Jul 4.3" 1.8" 2.5" 🚿 Regular watering
Aug 4.3" 2.8" 1.5" 💧 Light watering
Sep 4.3" 1.7" 2.6" 🚿 Regular watering
Oct 2.4" 0" ❄️ Dormant
Nov 1.5" 0" ❄️ Dormant
Dec 1.5" 0" ❄️ Dormant

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

Hot 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.

Hot Peppers needs ~1,378 GDD — county provides 1,914 GDD Excellent fit

Hot Peppers Planting Timeline — Boise County, ID

Hot Peppers Planting Calendar

Activity When Date Range
Start Indoors March 16 Mar 16 – Mar 30
Transplant Outdoors June 1 Jun 1 – Jun 15
Direct Sow May 25 May 25 – Jun 15
Harvest August 10 Aug 10 – Nov 16

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 Harvest
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

70–120 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 7a

📆 Growing Season

132 days in Boise County

Growing Tips for Hot Peppers in Boise County

Direct sow Hot Peppers outdoors after May 18 in Boise County when soil has warmed and frost danger has passed.

Your 132.0-day growing season in Boise County is tight for Hot Peppers (70.0-120.0 days to maturity). Start indoors and choose early-maturing varieties.

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

Boise County receives only 24" of rain annually. Hot Peppers needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 10-12 weeks before last frost as they germinate slowly. Use heat mats to maintain 80-85F soil temperature for germination. Stress plants slightly by reducing water to increase heat levels.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel
  • Kohlrabi

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Hot Peppers in Boise County, ID?

Boise County is in Zone 7a with an average last frost of May 18. Plan your Hot Peppers planting based on this frost date — see the calendar above for exact timing.

What planting zone is Boise County, ID?

Boise County, Idaho is in USDA Hardiness Zone 7a. The average last spring frost is May 18 and first fall frost is September 27.

🌱

Your Boise County Garden Planner — Free

A 24-page printable planner built for Boise 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 Boise 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.