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When to plant Lavender in Kankakee County County,

Kankakee County County's short 177-day growing season means one Lavender planting between May 11 and May 25. No fall crop in Zone 5b.

When to Plant Lavender in Kankakee County, IL

Lavender
Kankakee County, Illinois Zone 5b June

Your June planting checklist for Kankakee County, Illinois

June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Kankakee County, Illinois.

Avg. last frost April 20
Avg. first frost October 14
Soil temp (4") 68°F
Watering Moderate
Pest pressure High
Daylight 14.9 hrs
  1. Get lavender seeds going inside

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

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.

Kankakee County, Illinois is in USDA Zone 5b. The average last spring frost is April 20 and the first fall frost is October 14, giving you a growing season of approximately 177 days.

At an elevation of 1,113 feet, Kankakee County receives approximately 33.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Lavender during the growing season.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting Fragrant
Kankakee County, IL (Zone 5b) Moderate season
177 days
Last Spring Frost April 20
177 growing days
First Fall Frost October 14

Kankakee County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-6.8

Drainage

Well Drained

Lavender Planting Risk Windows

Early Start (70% safe) ✓ Fits season (35 days to spare)
Start indoors: Feb 4 Transplant: May 6 🌸 Bloom: Jul 15 – Sep 2
Recommended (50%) ✓ Fits season (37 days to spare)
Start indoors: Feb 9 Transplant: May 11 🌸 Bloom: Jul 20 – Sep 7
Safe Start (90%) ✓ Fits season (32 days to spare)
Start indoors: Feb 28 Transplant: May 30 🌸 Bloom: Aug 8 – Sep 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 Kankakee County

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

Soil pH

Your soil pH (6.1–6.8) is more acidic than Lavender prefers (6.5–7.5). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.9%) — 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
0.8″/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 1.3" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 1.3" 3.4" 0" ✅ Rainfall sufficient
May 1.3" 4.3" 0" ✅ Rainfall sufficient
Jun 1.3" 3.7" 0" ✅ Rainfall sufficient
Jul 1.3" 3.6" 0" ✅ Rainfall sufficient
Aug 1.3" 3.7" 0" ✅ Rainfall sufficient
Sep 1.3" 2.8" 0" ✅ Rainfall sufficient
Oct 1.3" 2.7" 0" ✅ Rainfall sufficient
Nov 2.5" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Kankakee 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 ~1,444 GDD — county provides 2,433 GDD Excellent fit

Lavender Planting Timeline — Kankakee County, IL

Lavender Planting Calendar

Activity When Date Range
Start Indoors February 9 Feb 9 – Feb 23
Transplant Outdoors May 11 May 11 – May 25
Bloom July 20 Jul 20 – Sep 7

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March
April
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: too_acidic

🗺️ USDA Zone

Zone 5b

📆 Growing Season

177 days in Kankakee County

Growing Tips for Lavender in Kankakee County

Direct sow Lavender outdoors after April 20 in Kankakee 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 Kankakee County, IL?

Kankakee County is in Zone 5b with an average last frost of April 20. Plan your Lavender planting based on this frost date — see the calendar above for exact timing.

What planting zone is Kankakee County, IL?

Kankakee County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 20 and first fall frost is October 14.

When should I plant Lavender in Kankakee County, ?

In Kankakee County, , plant Lavender after the last frost (around April 20) and before the first frost (around October 14). Best results when soil holds above 50°F.

What growing zone is Kankakee County, for Lavender?

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

Can Lavender grow in Kankakee County's climate?

Yes — Lavender grows well in Kankakee County's temperate climate. Kankakee County averages a 177-day frost-free season, with last frost around April 20 and first frost around October 14.

🌱

Your Kankakee County Garden Planner — Free

A 22-page printable planner built for Kankakee County (Zone 5b). 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 Kankakee 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.