When to Plant Lemon Balm in Vermilion County, IL
Lemon balm is a vigorous perennial herb with bright green, lemon-scented leaves. It makes a refreshing tea and is easy to grow but can spread aggressively.
Vermilion County, Illinois is in USDA Zone 5b. The average last spring frost is April 14 and the first fall frost is October 16, giving you a growing season of approximately 185 days.
At an elevation of 1,218 feet, Vermilion County receives approximately 31.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Lemon Balm during the growing season.
Vermilion County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-6.9
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
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Lemon Balm Planting Timeline — Vermilion County, IL
Lemon Balm Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 21 | Apr 21 – May 5 |
| Harvest | June 23 | Jun 23 – Aug 11 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Partial Shade (3-6 hours)
Water
Moderate — regular watering
Days to Maturity
60–70 days
Soil pH
5.5 – 7.5
USDA Zone
Zone 5b
Growing Season
185 days
Growing Tips for Vermilion County
Start from seed, cuttings, or divisions. Contain in pots or use barriers to prevent spreading. Harvest frequently to keep plants bushy and prevent flowering.
Companion Planting
Good Companions
Level Up Your Garden
Lemon Balm in Other Locations
Frequently Asked Questions
When should I plant Lemon Balm in Vermilion County, IL?
Vermilion County is in Zone 5b with an average last frost of April 14. Plan your Lemon Balm planting based on this frost date — see the calendar above for exact timing.
What planting zone is Vermilion County, IL?
Vermilion County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 14 and first fall frost is October 16.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Vermilion County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
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