One of the first steps you take when you are determining your gardening schedule is find your 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.

The earliest that you can plant campanula in San Diego can be estimated by looking at the USDA zone info.

Planting Calendar for Campanula

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

You can plant campanula a little earlier in the year because they are moderately cold tolerant.

The earliest that you can plant campanula in San Diego 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 campanula and expect a good harvest is probably October. You probably don't want to wait any later than that or else your campanula may not have a chance to really do well. Starting your campanula 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 San Diego. You can expect an average low temperature of 20°F in the coldest months of winter.

Always keep in mind that USDA zone info for San Diego is not always accurate and the actual date of last frost will vary from year to year. Half of the time in San Diego you get a frost after February 15 so just be sure to be ready to protect your campanula if you have a surprise late frost.

USDA Zone Info for San Diego

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in San Diego

You may be interested in your other planting guides for San Diego.