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When to plant Lavender in DeWitt County County,

In DeWitt County County, Lavender is a single-season spring crop — there's no second fall window. Plant April 29–May 13 for an 120-day harvest, finishing well before the October 17 first frost.

When to Plant Lavender in DeWitt County, IL

Lavender
DeWitt County, Illinois Zone 6a June

DeWitt County, Illinois gardeners: here's your June plan

Your garden in DeWitt County, Illinois is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost April 15
Avg. first frost October 17
Soil temp (4") 71°F
Watering Low
Pest pressure High
Daylight 14.8 hrs
  1. Start lavender indoors

    Starting these indoors now means sturdy transplants ready the moment your soil warms up.

Before July arrives, get these ready
  • First harvests: lavender

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Lavender (Lavandula angustifolia) is a fragrant Mediterranean sub-shrub prized for its silver-gray foliage and intensely aromatic purple flower spikes. A classic companion for roses and an unmatched pollinator magnet, lavender thrives in the exact conditions that challenge many plants: poor, rocky, alkaline soil with excellent drainage and full sun. English lavender is the most cold-hardy species, reliably perennial in Zones 5–9. Fresh or dried flowers are widely used in sachets, essential oils, culinary applications, and dried arrangements.

DeWitt County, Illinois is in USDA Zone 6a. The average last spring frost is April 15 and the first fall frost is October 17, giving you a growing season of approximately 185 days.

At an elevation of 801 feet, DeWitt County receives approximately 31.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Lavender to ensure they mature before fall.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting Fragrant
DeWitt County, IL (Zone 6a) Moderate season
185 days
Last Spring Frost April 15
185 growing days
First Fall Frost October 17

DeWitt County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7

Drainage

Well Drained

Lavender Planting Risk Windows

Early Start (70% safe) ✓ Fits season (44 days to spare)
Start indoors: Jan 30 Transplant: Apr 24 🌸 Bloom: Jul 3 – Aug 28
Recommended (50%) ✓ Fits season (45 days to spare)
Start indoors: Feb 4 Transplant: Apr 29 🌸 Bloom: Jul 8 – Sep 2
Safe Start (90%) ✓ Fits season (47 days to spare)
Start indoors: Feb 17 Transplant: May 12 🌸 Bloom: Jul 21 – Sep 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 DeWitt County

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

Soil pH

Your soil pH (6.1–7.0) overlaps with Lavender's range (6.5–7.5), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Lavender.

Organic Matter

Organic matter is excellent (5.0%) — Lavender will thrive.

How to Plant Lavender

0.5"
Planting Depth
18"
Between Plants
24"
Between Rows

Lavender Water Budget

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

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 1.4" 0" ❄️ Dormant
Feb 1.2" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 1.3" 2.6" 0" ✅ Rainfall sufficient
May 1.3" 4.1" 0" ✅ Rainfall sufficient
Jun 1.3" 4.3" 0" ✅ Rainfall sufficient
Jul 1.3" 3.2" 0" ✅ Rainfall sufficient
Aug 1.3" 3.6" 0" ✅ Rainfall sufficient
Sep 1.3" 2.7" 0" ✅ Rainfall sufficient
Oct 1.3" 2.3" 0" ✅ Rainfall sufficient
Nov 2.1" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in DeWitt 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 ~1,365 GDD — county provides 2,405 GDD Excellent fit

Lavender Planting Timeline — DeWitt County, IL

Lavender Planting Calendar

Activity When Date Range
Start Indoors February 4 Feb 4 – Feb 18
Transplant Outdoors April 29 Apr 29 – May 13
Bloom July 8 Jul 8 – Sep 2

Plant 0.5" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March
April Transplant Outdoors
May Transplant Outdoors
June
July Bloom
August Bloom
September Bloom
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.3"/week · Natural rainfall sufficient

📅 Days to Maturity

90–120 days

🧪 Soil pH

Needs 6.5–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

185 days in DeWitt County

Growing Tips for Lavender in DeWitt County

Direct sow Lavender outdoors after April 15 in DeWitt County when soil has warmed and frost danger has passed.

General growing tips

The single most important requirement for lavender success is excellent drainage — it will rot in heavy clay or wet winter soils before cold alone kills it. Amend with coarse sand or fine gravel if needed; raised beds work well in Zones 5–6. Start from rooted cuttings or transplants rather than seed for named cultivars. Transplant after last frost when soil is reliably warm (55°F+). Avoid rich or overly moist soils. Prune lightly after each flush of bloom, but never cut into old wood below the green growth zone — it will not regenerate from leafless woody stems. In Zones 5–6, mulch lightly with gravel (not bark/organic material which traps moisture) around the crown for winter protection. Year 2+ plants develop into full, mature shrubs with the most prolific bloom.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Lavender in DeWitt County, IL?

DeWitt County is in Zone 6a with an average last frost of April 15. Plan your Lavender planting based on this frost date — see the calendar above for exact timing.

What planting zone is DeWitt County, IL?

DeWitt County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 15 and first fall frost is October 17.

When should I plant Lavender in DeWitt County County, ?

In DeWitt County County, , plant Lavender after the last frost (around April 15) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is DeWitt County County, for Lavender?

DeWitt County County sits in USDA Zone 6a. Lavender grows reliably in zones 5a through 9b, so it's a good fit here.

Can Lavender grow in DeWitt County County's climate?

Yes — Lavender grows well in DeWitt County County's temperate climate. DeWitt County County averages a 185-day frost-free season, with last frost around April 15 and first frost around October 17.

🌱

Your DeWitt County Garden Planner — Free

A 22-page printable planner built for DeWitt 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 DeWitt County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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