When to plant Tomatoes in Union County, IL
Union County's climate puts the Tomatoes spring window between April 17 and May 8. most warm-season crops establish quickly once soil holds above 60°F.
When to Plant Tomatoes in Union 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.
Union County, Illinois is in USDA Zone 7a. The average last spring frost is April 10 and the first fall frost is October 21, giving you a growing season of approximately 194 days.
At an elevation of 1,017 feet, Union County receives approximately 34.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Tomatoes during the growing season.
Union County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
How Much Tomatoes to Grow
For a family of 4, plant approximately 12 tomatoes plants in about 24 sq ft. In Union County's 194-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Tomatoes Planting Timeline — Union County, IL
Tomatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 20 | Feb 20 – Mar 6 |
| Transplant Outdoors | April 24 | Apr 24 – May 8 |
| Direct Sow | April 17 | Apr 17 – May 8 |
| Harvest | June 26 | Jun 26 – Sep 4 |
Plant 0.5" deep · 24" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| 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
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 7a
📆 Growing Season
194 days in Union County
Growing Tips for Union 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
Check more plant combinations with our Companion Planting Checker →
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 Union County, IL?
Union County is in Zone 7a with an average last frost of April 10. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Union County, IL?
Union County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 10 and first fall frost is October 21.
When should I plant Tomatoes in Union County, IL?
In Union County, IL, plant Tomatoes after the last frost (around April 10) and before the first frost (around October 21). Best results when soil holds above 50°F.
What growing zone is Union County, IL for Tomatoes?
Union County sits in USDA Zone 7a. Tomatoes grows reliably in zones 3a through 11b, so it's a good fit here.
Can Tomatoes grow in Union County's climate?
Yes — Tomatoes grows well in Union County's temperate climate. Union County averages a 194-day frost-free season, with last frost around April 10 and first frost around October 21.
Your Union County Garden Planner — Free
A 22-page printable planner built for Union County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.