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 | May 24 | May 19 | May 15 | May 13 | May 10 | May 7 | April 28 |
| Fall frost on or before | September 30 | October 6 | October 8 | October 12 | October 17 | October 21 | October 22 |
| Frost-free period ≤ (days) | 139 | 146 | 147 | 149 | 154 | 160 | 165 |
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 | March 18 – April 1 |
| Sow peas, spinach, lettuce and radish outdoors (frost-tolerant) | April 15 – April 29 |
| Plant potatoes and onion sets | April 29 – May 13 |
| Transplant tomatoes and peppers; sow beans, corn, squash and cucumbers | May 20 – June 3 |
| Last sowing of quick crops (radish, lettuce, spinach) | August 29 – September 13 |
| Harvest or cover frost-tender crops | October 6 – October 13 |
| Plant garlic and spring bulbs | October 13 – November 10 |
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 19:07 UTC.
Data Source: Environment and Climate Change Canada Environment and Climate Change Canada Data Servers End-use Licence.
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