When to Plant Zucchini in Henderson 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.
Henderson County, Illinois is in USDA Zone 5a. The average last spring frost is April 17 and the first fall frost is October 17, giving you a growing season of approximately 183 days.
At an elevation of 1,278 feet, Henderson County receives approximately 41.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Zucchini to ensure they mature before fall.
Henderson County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-7.3
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 — Henderson County, IL
Zucchini Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 13 | Mar 13 – Mar 27 |
| Transplant Outdoors | May 1 | May 1 – May 15 |
| Direct Sow | April 24 | Apr 24 – May 15 |
| Harvest | June 19 | Jun 19 – Aug 14 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | 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 Henderson 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 Henderson County, IL?
Henderson County is in Zone 5a with an average last frost of April 17. Plan your Zucchini planting based on this frost date — see the calendar above for exact timing.
What planting zone is Henderson County, IL?
Henderson County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 17 and first fall frost is October 17.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Henderson County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
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