When to Plant Yarrow in Colleton County, SC
Top priorities for Colleton County, South Carolina gardeners in May
A quick May briefing for Colleton County, South Carolina gardeners — what's urgent, what's next, and what can wait.
To set up a strong June, finish these tasks
- 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.
Colleton County, South Carolina is in USDA Zone 8b. The average last spring frost is March 10 and the first fall frost is November 13, giving you a growing season of approximately 248 days.
At an elevation of 265 feet, Colleton County receives approximately 58.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96°F, so Yarrow may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Yarrow will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Yarrow root diseases.
Colleton County Soil Profile
Soil Type
Sandy Loam
Soil pH
4.9-6
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 Colleton County
How your county's soil matches Yarrow's growing requirements.
Soil pH
Your soil pH (4.9–6.0) is more acidic than Yarrow prefers (5.5–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in Colleton County warms quickly in spring but drains fast. Yarrow will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Yarrow prefers dry conditions but your soil drains poorly. Use raised beds or mounded rows to prevent root rot.
Organic Matter
Organic matter is moderate (2.1%). 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 | — | 4.6" | 0" | ❄️ Dormant |
| Feb | — | 5.3" | 0" | ❄️ Dormant |
| Mar | 2.2" | 6.2" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 4.2" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 5.8" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 5.7" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 5.5" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Dec | — | 4.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Colleton 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 — Colleton County, SC
Yarrow Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | March 17 | Mar 17 – Mar 31 |
| Harvest | June 16 | Jun 16 – Sep 1 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Transplant Outdoors |
| April | — |
| 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: too_acidic
🗺️ USDA Zone
Zone 8b
📆 Growing Season
248 days in Colleton County
Growing Tips for Yarrow in Colleton County
Direct sow Yarrow outdoors after March 10 in Colleton County when soil has warmed and frost danger has passed.
Sandy soil in Colleton County dries quickly — mulch Yarrow with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
With summer highs reaching 96°F in Colleton County, provide afternoon shade for Yarrow and water deeply in the morning.
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 Colleton County, SC?
Colleton County is in Zone 8b with an average last frost of March 10. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.
What planting zone is Colleton County, SC?
Colleton County, South Carolina is in USDA Hardiness Zone 8b. The average last spring frost is March 10 and first fall frost is November 13.
Your Colleton County Garden Planner — Free
A 24-page printable planner built for Colleton County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.