When to Plant Mint in Peterborough, ON
Mint is a vigorous perennial herb with refreshing, aromatic leaves used in teas, cocktails, and cooking. It spreads aggressively by underground runners.
Peterborough, Ontario is in USDA Zone 6b. The average last spring frost is April 13 and the first fall frost is October 17, giving you a growing season of approximately 187 days.
At an elevation of 656 feet, Peterborough receives approximately 40.6 inches of rainfall annually with predominantly clay loam soil. Summer highs average 81°F, so choose short-season varieties of Mint to ensure they mature before fall. Clay soil retains moisture well for Mint, but amend with compost to improve drainage and prevent root rot.
Peterborough Soil Profile
Soil Type
Clay Loam
Soil pH
6.0-7.0
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
Mint Planting Timeline — Peterborough, ON
Mint Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Harvest | June 22 | Jun 22 – Aug 31 |
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
High — keep soil consistently moist
Days to Maturity
60–90 days
Soil pH
6 – 7
USDA Zone
Zone 6b
Growing Season
187 days
Growing Tips for Peterborough
Always grow mint in containers or with underground barriers to control spreading. Harvest regularly to keep plants compact. Cut plants back in late summer for a fresh fall flush.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Mint in Other Locations
Frequently Asked Questions
When should I plant Mint in Peterborough, ON?
Peterborough is in Zone 6b with an average last frost of April 13. Plan your Mint planting based on this frost date — see the calendar above for exact timing.
What planting zone is Peterborough, ON?
Peterborough, Ontario is in USDA Hardiness Zone 6b. The average last spring frost is April 13 and first fall frost is October 17.
Plan Your Garden with Confidence
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