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When to Plant Valerian in Jefferson County, OH

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.

Jefferson County, Ohio is in USDA Zone 6a. The average last spring frost is April 23 and the first fall frost is October 29, giving you a growing season of approximately 189 days.

At an elevation of 1,017 feet, Jefferson County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Valerian during the growing season.

Jefferson County, OH (Zone 6a) Moderate season
189 days
Last Spring Frost April 23
189 growing days
First Fall Frost October 29

Jefferson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Apr 21 🍅 Harvest: Aug 25 – Nov 3
Recommended (50%) ✗ May not fit
Transplant: Apr 30 🍅 Harvest: Sep 3 – Nov 12
Safe Start (90%) ✗ May not fit
Transplant: May 16 🍅 Harvest: Sep 19 – Nov 28

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 Jefferson County

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

Soil pH

Your soil pH (5.9โ€“7.1) overlaps with Valerian's range (5.5โ€“7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Valerian.

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
0.9″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 695 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€” 1.6" 0" โ„๏ธ Dormant
Feb โ€” 1.9" 0" โ„๏ธ Dormant
Mar โ€” 2.6" 0" โ„๏ธ Dormant
Apr 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
May 4.3" 4.5" 0" โœ… Rainfall sufficient
Jun 4.3" 4.6" 0" โœ… Rainfall sufficient
Jul 4.3" 5.2" 0" โœ… Rainfall sufficient
Aug 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
Sep 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Oct 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Nov โ€” 2.8" 0" โ„๏ธ Dormant
Dec โ€” 2.1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Jefferson 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 ~2,175 GDD — county provides 2,740 GDD Good fit

Valerian Planting Timeline โ€” Jefferson County, OH

Valerian Planting Calendar

Activity When Date Range
Transplant Outdoors April 30 Apr 30 โ€“ May 14
Harvest September 3 Sep 3 โ€“ Nov 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 โ€”
September Harvest
October Harvest
November Harvest
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

120โ€“180 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

189 days in Jefferson County

Growing Tips for Valerian in Jefferson County

Direct sow Valerian outdoors after April 23 in Jefferson County when soil has warmed and frost danger has passed.

Your 189.0-day growing season in Jefferson 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 Jefferson County, OH?

Jefferson County is in Zone 6a with an average last frost of April 23. Plan your Valerian planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jefferson County, OH?

Jefferson County, Ohio is in USDA Hardiness Zone 6a. The average last spring frost is April 23 and first fall frost is October 29.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Jefferson County gardeners in Zone 6a 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 Jefferson County, OH. Local conditions may vary. Last updated: April 2026.