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When to Plant Valerian in Jo Daviess County, IL

Jo Daviess County, Illinois Zone 5a May

Your May planting checklist for Jo Daviess County, Illinois

May is a pivotal month for Jo Daviess County, Illinois gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 24
Avg. first frost October 11
Soil temp (4") 60°F
Watering Low
Pest pressure Low
Daylight 14.4 hrs
  1. Transplant valerian outside

    Water the tray well an hour before you transplant. Roots slide out cleanly and settle in faster.

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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.

Jo Daviess County, Illinois is in USDA Zone 5a. The average last spring frost is April 24 and the first fall frost is October 11, giving you a growing season of approximately 170 days.

At an elevation of 501 feet, Jo Daviess County receives approximately 35.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Valerian during the growing season.

Jo Daviess County, IL (Zone 5a) Moderate season
170 days
Last Spring Frost April 24
170 growing days
First Fall Frost October 11
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Jo Daviess County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Apr 23 🍅 Harvest: Aug 27 – Oct 8
Recommended (50%) ✗ May not fit
Transplant: May 1 🍅 Harvest: Sep 4 – Oct 16
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 Jo Daviess County

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

Soil pH

Your soil pH (5.9–7.3) overlaps with Valerian's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.2%) — 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
0.1″/week
Watering frequency Only during dry spells
Season total 190 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 1.3" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 4.3" 0" ✅ Rainfall sufficient
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 4.2" 0.1" 💧 Light watering
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 3.1" 1.2" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.2" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Jo Daviess County). Supplement amounts are based on average rainfall — 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" — 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.

Valerian needs ~2,288 GDD — county provides 2,592 GDD Good fit

Valerian Planting Timeline — Jo Daviess County, IL

Valerian Planting Calendar

Activity When Date Range
Transplant Outdoors May 1 May 1 – May 15
Harvest September 4 Sep 4 – Oct 16

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

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

120–180 days

🧪 Soil pH

Needs 5.5–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

170 days in Jo Daviess County

Growing Tips for Valerian in Jo Daviess County

Direct sow Valerian outdoors after April 24 in Jo Daviess County when soil has warmed and frost danger has passed.

Your 170.0-day growing season in Jo Daviess 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 Jo Daviess County, IL?

Jo Daviess County is in Zone 5a with an average last frost of April 24. Plan your Valerian planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jo Daviess County, IL?

Jo Daviess County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 24 and first fall frost is October 11.

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Your Jo Daviess County Garden Planner — Free

A 24-page printable planner built for Jo Daviess County (Zone 5a). 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 Jo Daviess County, IL. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.