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When to Plant Four-o-clock flower in Ontario, CA

One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Ontario you can determine when it's a good idea to plant four-o-clock flower by referring to the USDA zone info.


Planting Calendar for Four-o-clock flower

Frost tolerance for four-o-clock flower: Not tolerant of frost.
When to plant: After the last frost has passed.

It's not a good idea to plant four-o-clock flower until after the last frost when the weather gets warmer because they are not cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant four-o-clock flower
Possibly ok, but a risky time to plant four-o-clock flower
Probably not a good time to plant four-o-clock flower

The earliest that you can plant four-o-clock flower 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 four-o-clock flower and expect a good harvest is probably September. Any later than that and your four-o-clock flower may not have a chance to really do well. You can get started a couple of weeks earlier by starting your four-o-clock flower indoors.

Last Frost Date

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

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Ontario and it can change quite a bit from year to year. Half of the time in Ontario you get a frost after January 31 so just be sure to be ready to cover your four-o-clock flower in the event of one of those late frosts.

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.