One of the first steps you take when you are figuring out 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.

You can figure out when it's a good idea to plant basil in San Diego by looking at the USDA zone info.

Planting Calendar for Basil

Frost tolerance for basil:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since basil require warm weather you must wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant basil in San Diego is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant basil and expect a good harvest is probably September. If you wait any later than that and your basil may not have a chance to fully mature. If you are starting your basil indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In San Diego the average date of last frost happens on February 15. You should expect an average low temperature of 20°F in the coldest months of winter.

It's important to remember that USDA zone info for San Diego may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in San Diego you get a frost after February 15 be ready to cover your basil in the event of 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.