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When to plant Valerian in St. Clair County County,

Plant Valerian in St. Clair County County, between April 9 and April 23 — the only viable window. Zone 7a's short season (214 frost-free days) rules out a fall crop.

When to Plant Valerian in St. Clair 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.

St. Clair County, Illinois is in USDA Zone 7a. The average last spring frost is April 2 and the first fall frost is November 2, giving you a growing season of approximately 214 days.

At an elevation of 711 feet, St. Clair County receives approximately 34.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Valerian during the growing season.

St. Clair County, IL (Zone 7a) Long season
214 days
Last Spring Frost April 2
214 growing days
First Fall Frost November 2
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St. Clair County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.3

Drainage

Well Drained

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 1.5" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 3.8" 0.5" 💧 Light watering
Jun 4.3" 4" 0.3" 💧 Light watering
Jul 4.3" 3.8" 0.5" 💧 Light watering
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 4.3" 2.4" 1.9" 💧 Light watering
Dec 1.8" 0" ❄️ Dormant

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

Valerian Planting Timeline — St. Clair County, IL

Valerian Planting Calendar

Activity When Date Range
Transplant Outdoors April 9 Apr 9 – Apr 23
Harvest August 13 Aug 13 – Nov 19

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

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

120–180 days

🧪 Soil pH

Needs 5.5–7 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

214 days in St. Clair County

Growing Tips for St. Clair County

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 St. Clair County, IL?

St. Clair County is in Zone 7a with an average last frost of April 2. Plan your Valerian planting based on this frost date — see the calendar above for exact timing.

What planting zone is St. Clair County, IL?

St. Clair County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 2 and first fall frost is November 2.

When should I plant Valerian in St. Clair County County, ?

In St. Clair County County, , plant Valerian after the last frost (around April 2) and before the first frost (around November 2). Best results when soil holds above 50°F.

What growing zone is St. Clair County County, for Valerian?

St. Clair County County sits in USDA Zone 7a. Valerian grows reliably in zones 3a through 9b, so it's a good fit here.

Can Valerian grow in St. Clair County County's climate?

Yes — Valerian grows well in St. Clair County County's temperate climate. St. Clair County County averages a 214-day frost-free season, with last frost around April 2 and first frost around November 2.

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Your St. Clair County Garden Planner — Free

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

Sources & credits

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