When to Plant Yarrow in Colleton County, SC
Your June planting checklist for Colleton County, South Carolina
June is a pivotal month for Colleton County, South Carolina gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Pick yarrow
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
July will be here before you know it — start on
- First harvests: yarrow
Achillea millefolium (Yarrow) is a tough, drought-tolerant native perennial with aromatic finely-divided foliage and broad flat-topped flower clusters that serve as a landing platform for hundreds of beneficial insect species. Available in white (the species type) and a wide range of cultivars spanning yellow, gold, pink, salmon, and deep red. Spreads by rhizome to form ground-covering colonies; blooms from late spring through midsummer with reblooming into fall if deadheaded. Exceptional in hot, dry sites where other perennials fail.
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
Yarrow 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
Succession Planting Yarrow
Sow every 6.9 weeks. Last sowing by Aug 15 to harvest before frost.
Yarrow 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 |
|---|---|---|
| Start Indoors | January 13 | Jan 13 – Jan 27 |
| Transplant Outdoors | March 10 | Mar 10 – Mar 24 |
| Direct Sow | February 24 | Feb 24 – Mar 17 |
| Bloom | May 12 | May 12 – Oct 6 |
· 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 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
Start seeds indoors 8–10 weeks before last frost; seeds need light for germination — press onto soil surface, do not cover. Direct sow after last frost or divide established clumps in spring or fall. Thrives in poor, well-drained soil — rich soil and high fertility cause floppy stems and reduce flower count. Avoid overwatering; excellent drought tolerance once established. Deadhead spent clusters to encourage rebloom. Divide every 2–3 years to prevent center die-out and control spread. Year 2+ plants bloom most heavily; first-year plants may produce limited flowers. Dried flowers retain color well for arrangements.
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 22-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.