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When to Plant Valerian in Kankakee County, IL

Valerian is a tall perennial herb with fragrant white or pink flower clusters, valued for its root which is used as a natural sleep aid. It attracts pollinators and earthworms.

Kankakee County, Illinois is in USDA Zone 5a. 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 85ยฐF, providing good warmth for Valerian during the growing season.

Kankakee County, IL (Zone 5a) 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

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (0 days to spare)
Transplant: Apr 22 🍅 Harvest: Aug 26 – Oct 7
Recommended (50%) ✓ Fits season (2 days to spare)
Transplant: Apr 27 🍅 Harvest: Aug 31 – Oct 12
Safe Start (90%) ✗ May not fit
Transplant: May 16 🍅 Harvest: Sep 19 – Oct 31

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 Valerian's growing requirements.

Soil pH

Your soil pH (6.1โ€“6.8) is within Valerian's preferred range (5.5โ€“7.0).

Soil Texture

The silt loam soil in Kankakee County is excellent for Valerian โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.9%) โ€” Valerian will thrive.

How to Plant Valerian

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 319 gal / 100 sq ft

Monthly Watering Guide for Valerian

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

Month Valerian Needs Rainfall You Supplement Action
Jan โ€” 1.4" 0" โ„๏ธ Dormant
Feb โ€” 1.3" 0" โ„๏ธ Dormant
Mar โ€” 2.4" 0" โ„๏ธ Dormant
Apr 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
May 4.3" 4.3" 0" โœ… Rainfall sufficient
Jun 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Jul 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Aug 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Sep 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Oct 4.3" 2.7" 1.6" ๐Ÿ’ง Light watering
Nov โ€” 2.5" 0" โ„๏ธ Dormant
Dec โ€” 1.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Kankakee County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Valerian 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" โ€” every day above 50ยฐF 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.

Valerian needs ~2,062 GDD — county provides 2,433 GDD Good fit

Valerian Planting Timeline โ€” Kankakee County, IL

Valerian Planting Calendar

Activity When Date Range
Transplant Outdoors April 27 Apr 27 โ€“ May 11
Harvest August 31 Aug 31 โ€“ Oct 12

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

120โ€“180 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

177 days in Kankakee County

Growing Tips for Valerian in Kankakee County

Direct sow Valerian outdoors after April 20 in Kankakee County when soil has warmed and frost danger has passed.

Your 177.0-day growing season in Kankakee County is tight for Valerian (120.0-180.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

Start seeds indoors and transplant after last frost. Harvest roots in fall of the second year. Deadhead flowers unless you want self-seeding. Cats are attracted to valerian root.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Valerian in Kankakee County, IL?

Kankakee County is in Zone 5a with an average last frost of April 20. Plan your Valerian planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Kankakee County, IL?

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

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Kankakee County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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: April 2026.