Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Santa Rosa you can figure out when it's the best time to plant primroses by reviewing 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.

You can plant primroses quite a bit earlier in the year because they do well in cold.

The earliest that you can plant primroses in Santa Rosa 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 grow to maturity. 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 February 15 in Santa Rosa. In the coldest months of winter you can expect an average low temperature of 25°F.

Always keep in mind that USDA zone info for Santa Rosa may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Santa Rosa you get a frost after February 15 so be sure to be ready to protect your primroses in the event of one of those late frosts.

USDA Zone Info for Santa Rosa

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 Santa Rosa

You may be interested in your other planting guides for Santa Rosa.