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 Del Mar can be used to determine when it's the best time to plant penstemon.

Planting Calendar for Penstemon

Frost tolerance for penstemon:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since penstemon are moderately cold tolerant you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant penstemon 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 penstemon and expect a good harvest is probably October. If you wait any later than that and your penstemon may not have a chance to fully mature. If you are starting your penstemon indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in Del Mar. In the coldest months of winter you can 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 can change quite a bit from year to year. Half of the time in Del Mar it frosts late in the year after January 31 so be sure to be ready to protect your penstemon if you have a surprise late frost.

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.