When to Plant Kale in Ontario, CA

The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant kale in Ontario can be estimated by reviewing the USDA zone info.


Planting Calendar for Kale

Frost tolerance for kale: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

You can plant kale a little earlier in the year because they do well in moderate cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant kale
Possibly ok, but a risky time to plant kale
Probably not a good time to plant kale

The earliest that you can plant kale in Ontario is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant kale and expect a good harvest is probably October. If you wait any later than that and your kale may not have a chance to fully mature. You can get started a little bit earlier by starting your kale indoors.

Last Frost Date

In Ontario the average date of last frost happens on January 31. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Ontario is just an average the actual date of last frost will vary from year to year. Since half of the time in Ontario you get a frost after January 31 be ready to cover your kale in the event of a surprise late frost.

USDA Zone Info for Ontario

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)January 31
Average Date of First Frost (fall)December 15
Lowest Expected Low30°F
Highest Expected Low35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Ontario

You may be interested in your other planting guides for Ontario.