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In the garden now (2 November 2026)
Ottawa planting calendar
Bars show when each crop can go in and when a planting from that window is ready. The blue band is the frost season, from the average first autumn frost to the average last spring frost. Hover or tap a crop for details.
Sow indoorsSow or plant outdoorsHarvestFrost seasonToday
Swipe sideways to see the whole year →
Dates by crop
| Crop | Sow indoors | Sow / plant outdoors | Harvest |
|---|---|---|---|
| Tomato | Apr 1 – May 6 | May 27 – Jul 16 plant out | Jul 31 – Oct 1 |
| Pepper | Mar 28 – May 2 | Jun 6 – Jul 12 plant out | Aug 10 – Oct 1 |
| Eggplant (aubergine) | Apr 4 – May 9 | Jun 13 – Jul 8 plant out | Aug 19 – Oct 1 |
| Cucumber | May 4 – May 31 | Jun 1 – Jul 28 sow | Jul 22 – Oct 1 |
| Zucchini (courgette) | Apr 29 – May 26 | May 27 – Aug 1 sow | Jul 15 – Oct 1 |
| Pumpkin and winter squash | Apr 29 – May 26 | May 27 – Jun 25 sow | Aug 25 – Oct 1 |
| Watermelon | May 16 – Jun 12 | Jun 13 – Jul 5 sow | Aug 23 – Oct 1 |
| Sweet corn | – | May 18 – Jul 12 sow | Aug 4 – Oct 1 |
| Green beans | – | May 27 – Jul 28 sow | Jul 19 – Oct 1 |
| Peas | – | Apr 21 – May 9, Jul 26 – Aug 12 sow | Jun 28 – Jul 31, Sep 13 – Oct 9 |
| Lettuce | Mar 13 – Apr 10 | Apr 17 – Jun 16, Jul 11 – Aug 24 sow | Jun 16 – Oct 12 |
| Spinach | – | Apr 13 – May 30, Aug 11 – Sep 2 sow | Jun 12 – Jul 31, Sep 15 – Nov 1 |
| Kale | Mar 6 – Apr 10 | Apr 17 – Aug 23 sow | Jun 23 – Nov 16 |
| Cabbage | Mar 6 – Apr 10 | Apr 24 – Aug 10 plant out | Jul 6 – Oct 23 |
| Broccoli | Mar 6 – Apr 10 | Apr 24 – Aug 15 plant out | Jun 28 – Oct 16 |
| Carrots | – | Apr 24 – Aug 15 sow | Jul 2 – Nov 16 |
| Beets (beetroot) | – | Apr 24 – Aug 21 sow | Jun 25 – Oct 23 |
| Radishes | – | Apr 17 – Jun 29, Jul 25 – Sep 12 sow | May 29 – Aug 2, Aug 15 – Oct 16 |
| Onions | Feb 10 – Mar 17 | Apr 21 – Jul 14 plant out | Jul 23 – Oct 2 |
| Garlic | – | Sep 27 – Oct 16 sow | Jun 17 – Jul 7 |
| Potatoes | – | Apr 28 – Jul 18 sow | Jul 21 – Oct 2 |
| Swiss chard | – | Apr 28 – Aug 24 sow | Jun 22 – Oct 23 |
| Basil | Apr 25 – May 23 | Jun 6 – Aug 17 plant out | Jul 5 – Oct 1 |
| Cilantro (coriander) | – | Apr 24 – Jun 21, Jul 16 – Sep 2 sow | Jun 10 – Oct 16 |
| Parsley | Mar 3 – Apr 7 | Apr 28 – Aug 11 sow | Jul 7 – Nov 1 |
Dates are for a typical year and the middle of the window is the safest. Sow a little at a time across a window rather than all at once. Cold snaps, heat waves, frost pockets and city warmth all shift the real dates; watch the forecast.
Frost dates in Ottawa
- Average last spring frost
- May 7
- Late frost (1 year in 10)
- May 23 approx.
- Average first autumn frost
- October 2
- Early frost (1 year in 10)
- September 18 approx.
- Frost-free growing season
- 147 days
“Average” is the date with an even chance of a later (spring) or earlier (autumn) frost: a night at or below 0 °C (32 °F) at screen height. Tender crops go out a week or two after the spring date, which brings the risk down to about one year in ten.
Source: ECCC 1981–2010 normals, Ottawa Macdonald-Cartier Int'l A.
Climate at a glance
- Hardiness zone
- 4b estimate
- Average coldest winter night
- -29°C-21°F
- Warmest month
- July, highs 27°C81°F
- Coldest month
- January, lows -15°C5°F
- Crops with an outdoor window
- 25 of 25
The zone follows the USDA scheme: bands of the average lowest temperature of the year, 10 °F wide, split into a and b halves. Estimated from monthly climate normals; about one city in ten we checked comes out a full half-zone off. It tells you which perennials survive winter, not when to sow.
Temperature and rain by month
Average highAverage lowRainFreezing point
| Month | High | Low | Mean | Rain |
|---|---|---|---|---|
| January | -5°C22°F | -15°C5°F | -10°C14°F | 63 mm2.5 in |
| February | -3°C26°F | -14°C7°F | -9°C17°F | 56 mm2.2 in |
| March | 2°C36°F | -8°C18°F | -3°C27°F | 60 mm2.4 in |
| April | 11°C51°F | 0°C33°F | 6°C42°F | 79 mm3.1 in |
| May | 19°C67°F | 7°C45°F | 13°C56°F | 88 mm3.5 in |
| June | 24°C76°F | 13°C55°F | 19°C66°F | 93 mm3.7 in |
| July | 27°C81°F | 16°C60°F | 21°C70°F | 96 mm3.8 in |
| August | 26°C79°F | 15°C59°F | 21°C69°F | 92 mm3.6 in |
| September | 22°C72°F | 11°C51°F | 16°C62°F | 82 mm3.2 in |
| October | 14°C57°F | 5°C40°F | 9°C49°F | 89 mm3.5 in |
| November | 6°C43°F | -2°C29°F | 2°C36°F | 76 mm3.0 in |
| December | -1°C30°F | -9°C16°F | -5°C23°F | 77 mm3.0 in |
Monthly averages 1991–2020 from TerraClimate (about 4 km grid).