Blog

When to Plant Valerian in Knox County, TX

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.

Knox County, Texas is in USDA Zone 7b. The average last spring frost is March 24 and the first fall frost is November 12, giving you a growing season of approximately 233 days.

At an elevation of 1,847 feet, Knox County receives approximately 51.2 inches of rainfall annually with predominantly loam soil. Summer highs average 93ยฐF, providing good warmth for Valerian during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Valerian root diseases.

Knox County, TX (Zone 7b) Long season
233 days
Last Spring Frost March 24
233 growing days
First Fall Frost November 12

Knox County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Mar 24 🍅 Harvest: Jul 28 – Nov 3
Recommended (50%) ✓ Fits season (2 days to spare)
Transplant: Mar 31 🍅 Harvest: Aug 4 – Nov 10
Safe Start (90%) ✗ May not fit
Transplant: Apr 20 🍅 Harvest: Aug 24 – Nov 30

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 160 gal / 100 sq ft
Valerian needs ~2,962 GDD — county provides 4,601 GDD Excellent fit

Valerian Planting Timeline โ€” Knox County, TX

Valerian Planting Calendar

Activity When Date Range
Transplant Outdoors March 31 Mar 31 โ€“ Apr 14
Harvest August 4 Aug 4 โ€“ Nov 10

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

120โ€“180 days

Soil pH

5.5 โ€“ 7

USDA Zone

Zone 7b

Growing Season

233 days

Growing Tips for Knox 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

Level Up Your Garden

Frequently Asked Questions

When should I plant Valerian in Knox County, TX?

Knox County is in Zone 7b with an average last frost of March 24. Plan your Valerian planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Knox County, TX?

Knox County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 24 and first fall frost is November 12.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Knox County gardeners in Zone 7b 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 Knox County, TX. Local conditions may vary. Last updated: April 2026.