The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of estimating when it's possible to plant california poppy is to check out the USDA zone info for Ontario.

Planting Calendar for California Poppy

Frost tolerance for california poppy:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

California Poppy are barely cold tolerant which means that you can plant them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant california poppy 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 california poppy and expect a good harvest is probably September. You probably don't want to wait any later than that or else your california poppy may not have a chance to really do well. You can get started a few weeks earlier by starting your california poppy indoors.

Last Frost Date

The average date of last frost is January 31 in Ontario. In the coldest months of winter you should expect an average low temperature of 30°F.

Since the USDA zone info for Ontario is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Ontario you get surprised by a frost after January 31 so make sure that you are prepared to protect your california poppy in the event of a 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 Low	30°F
Highest Expected Low	35°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.