Manitoba · Growing Zone 3b
Gardeners in Selkirk, MB can expect the average last spring frost around May 23, and the first fall frost around September 20, based on historical Environment Canada frost data for the area. That gives Selkirk a frost-free growing season of roughly 120 days. Actual frost dates shift by a week or two year to year, so use this as a planning baseline rather than an exact guarantee, and always check your local forecast before moving tender plants outside.
You have your Selkirk frost dates. Now put them to work: GrowBlock counts back your indoor seed-starting weeks, marks your safe planting day, warns you before a frost, and lays your whole season out on one timeline.
Plan your Selkirk garden freeFree forever for one garden, no credit card. Built for Canadian gardeners.
Most warm-season crops (tomatoes, peppers, squash) need transplanting only after the last frost has passed, and are usually started indoors 6 to 8 weeks before that date. Cold-hardy crops (peas, lettuce, spinach) can often go in the ground a few weeks before the last frost. As Selkirk's first fall frost approaches in September, it's time to plan the last harvests for anything frost-sensitive still in the ground.
Approximate dates for common crops in Selkirk, worked out from the local last frost around May 23. Warm crops go out after frost, cold-hardy crops a few weeks before it, and anything with an indoor start is counted back from its sow date.
| Crop | Start indoors | Sow / transplant out | Approx. harvest |
|---|---|---|---|
| 🍅 Tomato | April 18 | June 6 | August 25 |
| 🌶️ Pepper | April 4 | June 6 | August 20 |
| 🥒 Cucumber | — | May 30 | July 27 |
| 🥬 Zucchini | — | May 30 | July 19 |
| 🥬 Lettuce | — | May 2 | June 16 |
| 🥬 Spinach | — | May 2 | June 19 |
| 🫛 Peas | — | May 2 | July 3 |
| 🥕 Carrots | — | May 2 | July 9 |
| 🫘 Bush beans | — | May 23 | July 12 |
| 🥬 Kale | April 4 | May 2 | June 26 |
Guideline dates from Selkirk's average frost window, not a guarantee. GrowBlock tunes these to each variety you plant and adjusts as you build your beds.
This calendar is a starting point. In GrowBlock every date is tuned to the exact varieties you plant and updates as you lay out your beds, and you can share the plan with whoever you garden with, changes show up for both of you.
Build your Selkirk garden planAround May 23 on average, though it can vary by a week or two either way depending on the year.
Selkirk is in zone 3b, with a frost-free season of about 120 days.
Now that you have your dates, here is how to put them to work through the season:
More how-to on the GrowBlock gardening blog.
See frost dates for all Canadian cities covered by GrowBlock.