When to plant Sunflower in Phillips County, AR
Sunflower planted in Phillips County between March 7 and March 28 matures in 70–100 days — well before the November 12 first frost.
When to Plant Sunflower in Phillips County, AR
Phillips County, Arkansas gardeners: here's your July plan
July is a pivotal month for Phillips County, Arkansas gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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It's harvest week for sunflower
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
A few tasks this July that'll pay off in August
- First harvests: sunflower
Sunflower (Helianthus annuus) is a fast-growing North American native annual famous for its towering stems and brilliant yellow heads. It thrives in full sun and heat, producing large, pollen-rich blooms that attract bees, butterflies, and seed-eating birds. Varieties range from 18-inch dwarfs to 12-foot giants and nearly every color except blue.
Phillips County, Arkansas is in USDA Zone 8a. The average last spring frost is March 14 and the first fall frost is November 12, giving you a growing season of approximately 243 days.
At an elevation of 678 feet, Phillips County receives approximately 50 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93°F, providing good warmth for Sunflower during the growing season.
Phillips County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.7
Drainage
Well Drained
Sunflower 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 Phillips County
How your county's soil matches Sunflower's growing requirements.
Soil pH
Your soil pH (5.6–6.7) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Phillips County is excellent for Sunflower — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.8%). Annual compost additions will help Sunflower.
How to Plant Sunflower
Succession Planting Sunflower
Sow every 8 weeks. Last sowing by Aug 04 to harvest before frost.
Sunflower Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Sunflower
Sunflower 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 | Sunflower Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.4" | 0" | ❄️ Dormant |
| Feb | — | 4" | 0" | ❄️ Dormant |
| Mar | 2.2" | 5.5" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 5.2" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.9" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Dec | — | 4.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Phillips County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sunflower 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.
Sunflower Planting Timeline — Phillips County, AR
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 21 | Feb 21 – Mar 7 |
| Transplant Outdoors | March 7 | Mar 7 – Mar 21 |
| Direct Sow | March 7 | Mar 7 – Mar 28 |
| Bloom | May 30 | May 30 – Oct 3 |
Plant 1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors 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
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 8a
📆 Growing Season
243 days in Phillips County
Growing Tips for Sunflower in Phillips County
Direct sow Sunflower outdoors after March 14 in Phillips County when soil has warmed and frost danger has passed.
Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct-sow 1 inch deep after last frost; germination takes 7-14 days at 65-75°F soil. Sunflowers dislike root disturbance so direct sowing is strongly preferred over transplanting. Plant in succession every 2 weeks for extended bloom. Stake tall varieties. Avoid overwatering — they tolerate drought once established. Birds will self-deadhead seed heads; leave them up through fall for wildlife.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Phillips County, AR?
Phillips County is in Zone 8a with an average last frost of March 14. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Phillips County, AR?
Phillips County, Arkansas is in USDA Hardiness Zone 8a. The average last spring frost is March 14 and first fall frost is November 12.
When should I plant Sunflower in Phillips County, AR?
In Phillips County, AR, plant Sunflower after the last frost (around March 14) and before the first frost (around November 12). Best results when soil holds above 50°F.
What growing zone is Phillips County, AR for Sunflower?
Phillips County sits in USDA Zone 8a. Sunflower grows reliably in zones 2a through 11b, so it's a good fit here.
Can Sunflower grow in Phillips County's climate?
Yes — Sunflower grows well in Phillips County's temperate climate. Phillips County averages a 243-day frost-free season, with last frost around March 14 and first frost around November 12.
Your Phillips County Garden Planner — Free
A 22-page printable planner built for Phillips 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.