One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of determining when to plant primroses is to look at the USDA zone info for Pleasanton.

Planting Calendar for Primroses

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

Primroses can survive in pretty solid cold which tells us that 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 Pleasanton 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. If you wait any later than that and 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 when the weather gets warmer is on February 15 in Pleasanton. In the coldest months of winter you should expect an average low temperature of 20°F.

Always keep in mind 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 Pleasanton and it will vary from year to year. Half of the time in Pleasanton there is a last frost after February 15 so make sure that you are prepared to protect your primroses if you have one of those late frosts.

USDA Zone Info for Pleasanton

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Pleasanton

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