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When to Plant Black radish in Ontario, OR

One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Ontario you will be able to figure out when it's possible to plant black radish.


Planting Calendar for Black radish

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

Since black radish are one of those plants that can tolerate a little bit of cold weather you can plant them a bit earlier in the year than other plants that might not handle the cold.

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

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

The last month that you can plant black radish and expect a good harvest is probably September. You probably don't want to wait any later than that or else your black radish may not have a chance to grow to maturity. If you are starting your black radish indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Ontario the average date of last frost happens on April 15. You should expect an average low temperature of -5°F in the coldest months of winter.

Always keep in mind that USDA zone info for Ontario may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Ontario you get a frost after April 15 be ready to cover your black radish if you have one of those late frosts.

USDA Zone Info for Ontario

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-5°F
Highest Expected Low0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Ontario

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