When to plant Corn in Delavan, IL
The best window to plant Corn in Delavan, is April 26–May 17, when soil warms to 50°F. Last frost typically hits April 19; first frost October 15.
When to Plant Corn in Delavan, IL
This month in Tazewell County, Illinois
June is a pivotal month for Tazewell County, Illinois 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 corn
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
Coming up in July — start thinking about
- First harvests: corn
Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.
Delavan, Illinois is in USDA Zone 6a. The average last spring frost is April 19 and the first fall frost is October 15, giving you a growing season of approximately 179 days.
At an elevation of 1,006 feet, Tazewell County receives approximately 40 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Corn during the growing season.
Delavan Soil Profile
Soil Type
Silt Loam
Soil pH
6.3-6.9
Drainage
Well Drained
Corn 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 Delavan
How your county's soil matches Corn's growing requirements.
Soil pH
Your soil pH (6.3–6.9) is within Corn's preferred range (6.0–7.0).
Soil Texture
The silt loam soil in Tazewell County is excellent for Corn — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.0%) — Corn will thrive.
How to Plant Corn
Succession Planting Corn
Sow every 6.9 weeks. Last sowing by Jul 07 to harvest before frost.
Corn Water Budget
Monthly Watering Guide for Corn
Corn needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Corn Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.9" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 2.6" | 0" | ❄️ Dormant |
| Apr | 6.5" | 3.9" | 2.6" | 💧 Light watering |
| May | 6.5" | 5.2" | 1.3" | 💧 Light watering |
| Jun | 6.5" | 5.1" | 1.4" | 💧 Light watering |
| Jul | 6.5" | 3.9" | 2.6" | 💧 Light watering |
| Aug | 6.5" | 4.7" | 1.8" | 💧 Light watering |
| Sep | 6.5" | 3.3" | 3.2" | 💧 Light watering |
| Oct | 6.5" | 3.1" | 3.4" | 🚿 Regular watering |
| Nov | — | 2.6" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Tazewell County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Corn 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.
Corn Planting Timeline — Delavan, IL
Corn Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | April 26 | Apr 26 – May 17 |
| Harvest | June 28 | Jun 28 – Aug 23 |
Plant 1" deep · 12" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Direct Sow |
| May | Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 1-2 times/week
📅 Days to Maturity
60–100 days
🧪 Soil pH
Needs 6–7 · Your soil: ideal
🗺️ USDA Zone
Zone 6a
📆 Growing Season
179 days in Tazewell County
Growing Tips for Corn in Delavan
Direct sow Corn outdoors after April 19 in Tazewell County when soil has warmed and frost danger has passed.
Common pests for Corn in this region include corn earworm and corn borers. Use row covers early in the season and inspect plants weekly.
General growing tips
Plant in blocks of at least 4 rows rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Corn in Other Locations
When should I plant Corn in Delavan, IL?
In Delavan, IL, plant Corn after the last frost (around April 19) and before the first frost (around October 15). Best results when soil holds above 50°F.
What growing zone is Delavan, IL for Corn?
Delavan sits in USDA Zone 6a. Corn grows reliably in zones 3a through 11b, so it's a good fit here.
Can Corn grow in Delavan's climate?
Yes — Corn grows well in Delavan's temperate climate. Delavan averages a 179-day frost-free season, with last frost around April 19 and first frost around October 15.
Your Tazewell County Garden Planner — Free
A 22-page printable planner built for Tazewell 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.