One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Irvine you should be able to figure out when you can plant calliopsis.

Planting Calendar for Calliopsis

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

You should not plant calliopsis until after the last frost has passed because they require warm weather.

The earliest that you can plant calliopsis 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 calliopsis and expect a good harvest is probably September. Any later than that and your calliopsis may not have a chance to grow to maturity. If you are starting your calliopsis indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Irvine. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Irvine is just an average the actual date of last frost is different every year. Half of the time in Irvine you get surprised by a frost after January 31 so make sure that you are ready to cover your calliopsis 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.