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Last Frost Date for Hamilton, ON

Ontario · Growing Zone 6b

Last Spring Frost
April 18
First Fall Frost
November 1
Growing Season
197 days
Hardiness Zone
6b

Gardeners in Hamilton, ON can expect the average last spring frost around April 18, and the first fall frost around November 1, based on historical Environment Canada frost data for the area. That gives Hamilton a frost-free growing season of roughly 197 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 Hamilton 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.

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What this means for planning

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 Hamilton's first fall frost approaches in November, it's time to plan the last harvests for anything frost-sensitive still in the ground.

Hamilton planting calendar

Approximate dates for common crops in Hamilton, worked out from the local last frost around April 18. 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.

CropStart indoorsSow / transplant outApprox. harvest
🍅 Tomato March 14 May 2 July 21
🌶️ Pepper February 28 May 2 July 16
🥒 Cucumber — April 25 June 22
🥬 Zucchini — April 25 June 14
🥬 Lettuce — March 28 May 12
🥬 Spinach — March 28 May 15
🫛 Peas — March 28 May 29
🥕 Carrots — March 28 June 4
🫘 Bush beans — April 18 June 7
🥬 Kale February 28 March 28 May 22

Guideline dates from Hamilton'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 Hamilton garden plan

Frequently asked questions

When is the last frost in Hamilton, ON?

Around April 18 on average, though it can vary by a week or two either way depending on the year.

What growing zone is Hamilton?

Hamilton is in zone 6b, with a frost-free season of about 197 days.

Gardening guides

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.

Frost dates for other cities

See frost dates for all Canadian cities covered by GrowBlock.