1981–2010 normals; ECCC quality code “A” (A = WMO “3 and 5 rule”; B ≥ 25 years; C ≥ 20 years; D ≥ 15 years of data). An average is not a guarantee: a late frost is still possible.
| 10% | 25% | 33% | 50% | 66% | 75% | 90% | |
|---|---|---|---|---|---|---|---|
| Spring frost (0 °C or lower) on or after | July 9 | June 29 | June 27 | June 25 | June 21 | June 19 | June 16 |
| Fall frost on or before | August 9 | August 16 | August 19 | August 26 | August 30 | September 3 | September 8 |
| Frost-free period ≤ (days) | 34 | 48 | 51 | 61 | 67 | 72 | 78 |
Example: the spring 10% column is the date after which a frost occurs in only one year in ten.
| Start tomatoes, peppers and eggplant indoors | April 27 – May 11 |
| Sow peas, spinach, lettuce and radish outdoors (frost-tolerant) | May 25 – June 8 |
| Plant potatoes and onion sets | June 8 – June 22 |
| Transplant tomatoes and peppers; sow beans, corn, squash and cucumbers | June 29 – July 13 |
| Last sowing of quick crops (radish, lettuce, spinach) | July 15 – July 30 |
| Harvest or cover frost-tender crops | August 22 – August 29 |
| Plant garlic and spring bulbs | August 29 – September 26 |
General gardening rules of thumb computed from this station's average last/first frost dates; they are not ECCC data. Adjust to local conditions and seed-packet instructions.
Environment and Climate Change Canada — Canadian Climate Normals 1981–2010 (station data, MSC Datamart) (30-year averages; not updated). Retrieved 2026-10-18 19:08 UTC.
Data Source: Environment and Climate Change Canada Environment and Climate Change Canada Data Servers End-use Licence.
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