Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By referring to the USDA zone info for Del Mar you should be able to determine when it's possible to 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 are one of those plants that can tolerate quite a bit of cold weather 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 primula in Del Mar 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 really do well. You can get started a little bit earlier by starting your primula indoors.

Last Frost Date

On average all chance of frost has passed is on January 31 in Del Mar. In the coldest months of winter you should expect an average low temperature of 30°F.

Since the USDA zone info for Del Mar is just an average the actual date of last frost will vary from year to year. Since half of the time in Del Mar last frost occurs after January 31 be ready to cover your primula in the event of one of those late frosts.

USDA Zone Info for Del Mar

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 Del Mar

You may be interested in your other planting guides for Del Mar.