When to Plant Yarrow in Jefferson County, IL
Yarrow is a drought-tolerant perennial herb with feathery foliage and flat-topped flower clusters in white, yellow, pink, or red. It attracts beneficial insects and is used in herbal medicine.
Jefferson County, Illinois is in USDA Zone 6a. The average last spring frost is April 9 and the first fall frost is October 20, giving you a growing season of approximately 194 days.
At an elevation of 509 feet, Jefferson County receives approximately 34 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Yarrow during the growing season.
Jefferson County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7.1
Drainage
Well Drained
Plant Planting Risk Windows
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 Yarrow's growing requirements.
Soil pH
Your soil pH (6.1–7.1) overlaps with Yarrow's range (5.5–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Jefferson County is excellent for Yarrow — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.2%) — Yarrow will thrive.
How to Plant Yarrow
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Yarrow Planting Timeline — Jefferson County, IL
Yarrow Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 16 | Apr 16 – Apr 30 |
| Harvest | July 16 | Jul 16 – Oct 1 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | — |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 5.5–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6a
📆 Growing Season
194 days in Jefferson County
Growing Tips for Yarrow in Jefferson County
Direct sow Yarrow outdoors after April 09 in Jefferson County when soil has warmed and frost danger has passed.
Common pests for Yarrow in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow or start from divisions. Yarrow thrives in poor soil and is very drought-tolerant. Deadhead to encourage reblooming. Divide clumps every 3 years.
Companion Planting
Good Companions
Level Up Your Garden
Yarrow in Other Locations
Frequently Asked Questions
When should I plant Yarrow in Jefferson County, IL?
Jefferson County is in Zone 6a with an average last frost of April 9. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jefferson County, IL?
Jefferson County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 9 and first fall frost is October 20.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Jefferson County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.
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