When to plant Sunflower in Kankakee County County,
The best window to plant Sunflower in Kankakee County County, is April 27–May 18, when soil warms to 50°F. Last frost typically hits April 20; first frost October 14.
When to Plant Sunflower in Kankakee 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.
Kankakee County, Illinois is in USDA Zone 5b. The average last spring frost is April 20 and the first fall frost is October 14, giving you a growing season of approximately 177 days.
At an elevation of 1,113 feet, Kankakee County receives approximately 33.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Sunflower during the growing season.
Kankakee County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-6.8
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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| May | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Jul | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Aug | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Sep | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Oct | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 1.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Kankakee County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sunflower Planting Timeline — Kankakee 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 5 |
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 5b
📆 Growing Season
177 days in Kankakee County
Growing Tips for Kankakee 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 Kankakee County, IL?
Kankakee County is in Zone 5b 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 Kankakee County, IL?
Kankakee County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 20 and first fall frost is October 14.
When should I plant Sunflower in Kankakee County County, ?
In Kankakee County County, , plant Sunflower after the last frost (around April 20) and before the first frost (around October 14). Best results when soil holds above 50°F.
What growing zone is Kankakee County County, for Sunflower?
Kankakee County County sits in USDA Zone 5b. Sunflower grows reliably in zones 2a through 11b, so it's a good fit here.
Can Sunflower grow in Kankakee County County's climate?
Yes — Sunflower grows well in Kankakee County County's temperate climate. Kankakee County County averages a 177-day frost-free season, with last frost around April 20 and first frost around October 14.
Your Kankakee County Garden Planner — Free
A 22-page printable planner built for Kankakee County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.