When to plant Sunflower in Fulton County, IL
Fulton County gardeners should plant Sunflower between April 27 and May 18 in spring. With Fulton County's Zone 6a climate (last frost April 20), Sunflower needs 70–100 days to mature — plant by July 8 for a full harvest.
When to Plant Sunflower in Fulton County, IL
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.
Fulton County, Illinois is in USDA Zone 6a. The average last spring frost is April 20 and the first fall frost is October 16, giving you a growing season of approximately 179 days.
At an elevation of 1,162 feet, Fulton County receives approximately 39.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Sunflower to ensure they mature before fall.
Fulton County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-6.7
Drainage
Well Drained
Monthly Watering Guide for Sunflower
Sunflower needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Sunflower Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| May | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Sep | 4.3" | 3.3" | 1" | 💧 Light watering |
| Oct | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 2.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Fulton County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sunflower Planting Timeline — Fulton County, IL
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 30 | Mar 30 – Apr 13 |
| Transplant Outdoors | April 27 | Apr 27 – May 11 |
| Direct Sow | April 27 | Apr 27 – May 18 |
| Bloom | July 20 | Jul 20 – Oct 12 |
Plant 1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 6a
📆 Growing Season
179 days in Fulton County
Growing Tips for Fulton County
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 Fulton County, IL?
Fulton County is in Zone 6a with an average last frost of April 20. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Fulton County, IL?
Fulton County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 20 and first fall frost is October 16.
When should I plant Sunflower in Fulton County, IL?
In Fulton County, IL, plant Sunflower after the last frost (around April 20) and before the first frost (around October 16). Best results when soil holds above 50°F.
What growing zone is Fulton County, IL for Sunflower?
Fulton County sits in USDA Zone 6a. Sunflower grows reliably in zones 2a through 11b, so it's a good fit here.
Can Sunflower grow in Fulton County's climate?
Yes — Sunflower grows well in Fulton County's temperate climate. Fulton County averages a 179-day frost-free season, with last frost around April 20 and first frost around October 16.
Your Fulton County Garden Planner — Free
A 22-page printable planner built for Fulton County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.