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.

The USDA zone info for Pleasant Hill should be looked at to determine when you can plant primula.

Planting Calendar for Primula

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

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

The earliest that you can plant primula in Pleasant Hill 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. If you wait any later than that and your primula may not have a chance to grow to maturity. Starting your primula indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Pleasant Hill. In the coldest months of winter you can expect an average low temperature of 25°F.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Pleasant Hill and it can change quite a bit from year to year. Since half of the time in Pleasant Hill it frosts late in the year after February 15 be ready to cover your primula in the event of a late frost.

USDA Zone Info for Pleasant Hill

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 Pleasant Hill

You may be interested in your other planting guides for Pleasant Hill.