One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

You should be able to estimate when it's possible to plant primroses by referring to the USDA zone info for Campbell.

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 a lot earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant primroses in Campbell 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. You can get started a little bit earlier by starting your primroses indoors.

Last Frost Date

On average the last frost is on February 15 in Campbell. In the coldest months of winter you can expect an average low temperature of 25°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Campbell and it changes from year to year. Half of the time in Campbell you get a frost after February 15 so make sure that you are prepared to protect your primroses in the event of a surprise late frost.

USDA Zone Info for Campbell

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 Campbell

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