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.

In Irvine you can estimate when to plant basil by reviewing the USDA zone info.

Planting Calendar for Basil

Frost tolerance for basil:	Not tolerant of frost.
When to plant:	After the last frost.

Since basil do not do well in cold weather you have to wait until after the last frost has passed before you can plant them.

The earliest that you can plant basil in Irvine is February. However, you really should wait until March 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. Any later than that and your basil may not have a chance to grow to maturity. If you are starting your basil indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost has passed is on January 31 in Irvine. You can expect an average low temperature of 30°F in the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Irvine and it can change quite a bit from year to year. Half of the time in Irvine you get surprised by a frost after January 31 so always be ready to protect your basil if you have a surprise late frost.

USDA Zone Info for Irvine

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 Irvine

You may be interested in your other planting guides for Irvine.