When to Plant Yarrow in Vernon Parish, LA
May in Vernon Parish, Louisiana — your action list
Welcome to May in Zone 9a. These are the moves that will have the biggest impact on your growing season.
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.
Vernon Parish, Louisiana is in USDA Zone 9a. The average last spring frost is March 5 and the first fall frost is November 16, giving you a growing season of approximately 256 days.
At an elevation of 481 feet, Vernon Parish receives approximately 54.2 inches of rainfall annually with predominantly loam soil. Summer highs average 97°F, so Yarrow may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Yarrow root diseases.
Vernon Parish Soil Profile
Soil Type
Loam
Soil pH
6.1-7.2
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 Vernon Parish
How your county's soil matches Yarrow's growing requirements.
Soil pH
Your soil pH (6.1–7.2) overlaps with Yarrow's range (5.5–7.0), though not a perfect match.
Soil Texture
The loam soil in Vernon Parish is excellent for Yarrow — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Yarrow.
Organic Matter
Organic matter is moderate (2.5%). 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 | — | 4.7" | 0" | ❄️ Dormant |
| Mar | 2.2" | 5.4" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.7" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.7" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 5.8" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 5.1" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Dec | — | 4.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Vernon Parish). 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 — Vernon Parish, LA
Yarrow Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | March 12 | Mar 12 – Mar 26 |
| Harvest | June 11 | Jun 11 – Aug 27 |
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 | — |
| 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 9a
📆 Growing Season
256 days in Vernon Parish
Growing Tips for Yarrow in Vernon Parish
Direct sow Yarrow outdoors after March 05 in Vernon Parish when soil has warmed and frost danger has passed.
With summer highs reaching 97°F in Vernon Parish, 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 Vernon Parish, LA?
Vernon Parish is in Zone 9a with an average last frost of March 5. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.
What planting zone is Vernon Parish, LA?
Vernon Parish, Louisiana is in USDA Hardiness Zone 9a. The average last spring frost is March 5 and first fall frost is November 16.
Your Vernon Parish Garden Planner — Free
A 24-page printable planner built for Vernon Parish (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.