One of the best tools that you have as gardeners to help us determine 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 best time to plant primula in Zone 10a should be figured out by using the USDA zone info.

Planting Calendar for Primula

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

Since primula are very cold tolerant you can plant them much earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant primula in Zone 10a 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. If you are starting your primula indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Zone 10a. It might get as low as 30°F during the coldest months of winter.

Always keep in mind that USDA zone info for Zone 10a is just an average and the actual date of last frost is different every year. Half of the time in Zone 10a you get a frost after January 31 so make sure that you are prepared to protect your primula if you have a late frost.

USDA Zone Info for Zone 10a

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Zone 10a

You may be interested in your other planting guides for Zone 10a.