When to Plant Zucchini in Henry County, IL
Zucchini is an incredibly prolific summer squash that can produce an abundance of fruit from just a few plants. It is versatile in the kitchen from grilling to baking.
Henry County, Illinois is in USDA Zone 5a. The average last spring frost is April 16 and the first fall frost is October 16, giving you a growing season of approximately 183 days.
At an elevation of 593 feet, Henry County receives approximately 31.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Zucchini during the growing season.
Henry County Soil Profile
Soil Type
Silt Loam
Soil pH
6.3-7.2
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.
Plant Water Budget
Zucchini Planting Timeline — Henry County, IL
Zucchini Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 12 | Mar 12 – Mar 26 |
| Transplant Outdoors | April 30 | Apr 30 – May 14 |
| Direct Sow | April 23 | Apr 23 – May 14 |
| Harvest | June 18 | Jun 18 – Aug 13 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
45–60 days
Soil pH
6 – 7.5
USDA Zone
Zone 5a
Growing Season
183 days
Growing Tips for Henry County
Direct sow after last frost. Harvest when fruits are 6-8 inches long for best flavor and texture. Check plants daily in summer as fruits can double in size overnight.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Zucchini in Other Locations
Frequently Asked Questions
When should I plant Zucchini in Henry County, IL?
Henry County is in Zone 5a with an average last frost of April 16. Plan your Zucchini planting based on this frost date — see the calendar above for exact timing.
What planting zone is Henry County, IL?
Henry County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 16 and first fall frost is October 16.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Henry County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.