When to Plant Tomatoes in Kendall County, IL
Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.
Kendall County, Illinois is in USDA Zone 5a. The average last spring frost is April 20 and the first fall frost is October 17, giving you a growing season of approximately 180 days.
At an elevation of 708 feet, Kendall County receives approximately 38.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Tomatoes during the growing season.
Kendall County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-6.8
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
Tomatoes Planting Timeline — Kendall County, IL
Tomatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 23 | Feb 23 – Mar 9 |
| Transplant Outdoors | May 4 | May 4 – May 18 |
| Direct Sow | April 27 | Apr 27 – May 18 |
| Harvest | July 6 | Jul 6 – Sep 14 |
Plant 0.5" deep · 24" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
60–85 days
Soil pH
6 – 7
USDA Zone
Zone 5a
Growing Season
180 days
Growing Tips for Kendall County
Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.
Tomatoes in Other Locations
Frequently Asked Questions
When should I plant Tomatoes in Kendall County, IL?
Kendall County is in Zone 5a with an average last frost of April 20. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Kendall County, IL?
Kendall County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 20 and first fall frost is October 17.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Kendall County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
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