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.

In Fontana you can determine when you can plant primroses by using the USDA zone info.

Planting Calendar for Primroses

Frost tolerance for primroses:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since primroses do well in cold you can plant them a lot earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant primroses in Fontana 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 primroses and expect a good harvest is probably October. You probably don't want to wait any later than that or else your primroses may not have a chance to really do well. If you are starting your primroses indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost has passed is on January 31 in Fontana. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Fontana is just an average the actual date of last frost will vary from year to year. Half of the time in Fontana you get a frost after January 31 so just be sure to be ready to cover your primroses in the event of one of those late frosts.

USDA Zone Info for Fontana

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 Fontana

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