When to Plant Yarrow in Shelby County, TN
May in the garden — Shelby County, Tennessee
Here's what deserves your attention in Shelby County, Tennessee this month. Everything below is tailored to Zone 8a and timed around your local frost dates.
Coming up in June — start thinking about
- First harvests: yarrow
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.
Shelby County, Tennessee is in USDA Zone 8a. The average last spring frost is March 21 and the first fall frost is November 5, giving you a growing season of approximately 229 days.
At an elevation of 3,465 feet, Shelby County receives approximately 45.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Yarrow during the growing season.
Shelby County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-7
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 Shelby County
How your county's soil matches Yarrow's growing requirements.
Soil pH
Your soil pH (5.3–7.0) overlaps with Yarrow's range (5.5–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Shelby County is excellent for Yarrow — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.1%). Annual compost additions will help Yarrow.
How to Plant Yarrow
Plant Water Budget
Monthly Watering Guide for Yarrow
Yarrow needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Yarrow Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.3" | 0" | ❄️ Dormant |
| Feb | — | 3.8" | 0" | ❄️ Dormant |
| Mar | 2.2" | 4.2" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 2.9" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 5.1" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.7" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Shelby County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Yarrow 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.
Yarrow Planting Timeline — Shelby County, TN
Yarrow Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | March 28 | Mar 28 – Apr 11 |
| Harvest | June 27 | Jun 27 – Sep 12 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Transplant Outdoors |
| April | Transplant Outdoors |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| 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 8a
📆 Growing Season
229 days in Shelby County
Growing Tips for Yarrow in Shelby County
Direct sow Yarrow outdoors after March 21 in Shelby 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
Check more plant combinations with our Companion Planting Checker →
Yarrow in Other Locations
Frequently Asked Questions
When should I plant Yarrow in Shelby County, TN?
Shelby County is in Zone 8a with an average last frost of March 21. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.
What planting zone is Shelby County, TN?
Shelby County, Tennessee is in USDA Hardiness Zone 8a. The average last spring frost is March 21 and first fall frost is November 5.
Your Shelby County Garden Planner — Free
A 24-page printable planner built for Shelby County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.