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When to Plant Lavender in Nez Perce County, ID

Nez Perce County, Idaho Zone 6b April

April to-do list for Nez Perce County, Idaho

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

Avg. last frost May 12
Avg. first frost September 26
Soil temp (4") 37°F
Watering High
Pest pressure Low
Daylight 13.3 hrs
May will be here before you know it — start on
  • Transplants going out: lavender

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Lavender is a fragrant perennial herb with silvery foliage and purple flower spikes. It is prized for its essential oils, culinary uses, and ornamental beauty.

Nez Perce County, Idaho is in USDA Zone 6b. The average last spring frost is May 12 and the first fall frost is September 26, giving you a growing season of approximately 137 days.

At an elevation of 4,819 feet, Nez Perce County receives approximately 16.7 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Lavender during the growing season. With low rainfall, drip irrigation is essential for growing Lavender successfully. Mulch heavily to conserve soil moisture.

Nez Perce County, ID (Zone 6b) Short season
137 days
Last Spring Frost May 12
137 growing days
First Fall Frost September 26

Nez Perce County Soil Profile

Soil Type

Loam

Soil pH

6.6-8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 14 🍅 Harvest: Aug 13 – Nov 26
Recommended (50%) ✗ May not fit
Transplant: May 19 🍅 Harvest: Aug 18 – Dec 1
Safe Start (90%) ✗ May not fit
Transplant: Jun 13 🍅 Harvest: Sep 12 – Dec 26

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 Nez Perce County

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

Soil pH

Your soil pH (6.6–8.0) is within Lavender's preferred range (6.5–8.0).

Soil Texture

The loam soil in Nez Perce County is excellent for Lavender — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

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

How to Plant Lavender

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

Plant Water Budget

Plant needs
0.3″/week
Rainfall provides
0.5″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Lavender

Lavender needs approximately 0.3 inches of water per week (1.3" per month). Here's how your county's rainfall compares month by month.

Month Lavender Needs Rainfall You Supplement Action
Jan 1.2" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 1.5" 0" ❄️ Dormant
Apr 1.7" 0" ❄️ Dormant
May 1.3" 1.8" 0" ✅ Rainfall sufficient
Jun 1.3" 1.2" 0.1" 💧 Light watering
Jul 1.3" 1.5" 0" ✅ Rainfall sufficient
Aug 1.3" 1.7" 0" ✅ Rainfall sufficient
Sep 1.3" 1.2" 0.1" 💧 Light watering
Oct 1.7" 0" ❄️ Dormant
Nov 1.1" 0" ❄️ Dormant
Dec 1.1" 0" ❄️ Dormant

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

Lavender 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.

Lavender needs ~2,538 GDD — county provides 2,397 GDD Tight fit

Lavender Planting Timeline — Nez Perce County, ID

Lavender Planting Calendar

Activity When Date Range
Transplant Outdoors May 19 May 19 – Jun 2
Harvest August 18 Aug 18 – Dec 1

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

Month-by-Month Timeline

MonthActivities
January
February
March
April
May Transplant Outdoors
June Transplant Outdoors
July
August Harvest
September Harvest
October Harvest
November Harvest
December Harvest

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.3"/week · Natural rainfall sufficient

📅 Days to Maturity

90–200 days

🧪 Soil pH

Needs 6.5–8 · Your soil: ideal

🗺️ USDA Zone

Zone 6b

📆 Growing Season

137 days in Nez Perce County

Growing Tips for Lavender in Nez Perce County

Direct sow Lavender outdoors after May 12 in Nez Perce County when soil has warmed and frost danger has passed.

Your 137.0-day growing season in Nez Perce County is tight for Lavender (90.0-200.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

Plant in well-drained, sandy soil. Avoid heavy mulching around the crown. Prune after flowering but do not cut into old wood. Lavender resents wet winter conditions.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Lavender in Nez Perce County, ID?

Nez Perce County is in Zone 6b with an average last frost of May 12. Plan your Lavender planting based on this frost date — see the calendar above for exact timing.

What planting zone is Nez Perce County, ID?

Nez Perce County, Idaho is in USDA Hardiness Zone 6b. The average last spring frost is May 12 and first fall frost is September 26.

🌱

Your Nez Perce County Garden Planner — Free

A 24-page printable planner built for Nez Perce County (Zone 6b). 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 Nez Perce County, ID. Local conditions may vary. Last updated: April 2026.

Sources & credits

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