One of the first steps you take when you are making a decision about your gardening schedule is find your 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.

One way of getting a good idea when to plant primula is to examine the USDA zone info for Gridley.

Planting Calendar for Primula

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

Primula are one of those plants that can tolerate quite a bit of cold weather which tells us that you can get them planted much earlier than plants that are more sensitive to the cold.

The earliest that you can plant primula in Gridley 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 primula and expect a good harvest is probably October. You probably don't want to wait any later than that or else your primula may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your primula indoors.

Last Frost Date

In Gridley the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Gridley and it can change quite a bit from year to year. Half of the time in Gridley you get surprised by a frost after February 15 so always be ready to protect your primula if you have one of those late frosts.

USDA Zone Info for Gridley

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Gridley

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