1981–2010 normals; ECCC quality code “C” (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 4 | June 23 | June 21 | June 13 | June 11 | June 9 | June 4 |
| Fall frost on or before | July 26 | August 22 | August 25 | August 31 | September 6 | September 9 | September 23 |
| Frost-free period ≤ (days) | 36 | 60 | 68 | 75 | 82 | 88 | 112 |
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 21 – May 5 |
| Sow peas, spinach, lettuce and radish outdoors (frost-tolerant) | May 19 – June 2 |
| Plant potatoes and onion sets | June 2 – June 16 |
| Transplant tomatoes and peppers; sow beans, corn, squash and cucumbers | June 23 – July 7 |
| 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 19:14 UTC.
Data Source: Environment and Climate Change Canada Environment and Climate Change Canada Data Servers End-use Licence.
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