One of the first steps you take when you are estimating 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 USDA zone info for Tustin can be looked at to estimate when you can plant columbine.

Planting Calendar for Columbine

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

You can plant columbine a bit earlier in the year because they do well in moderate cold.

The earliest that you can plant columbine in Tustin 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 columbine and expect a good harvest is probably October. Any later than that and your columbine may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your columbine indoors.

Last Frost Date

The average date of last frost is January 31 in Tustin. In the coldest months of winter you should expect an average low temperature of 30°F.

Since the USDA zone info for Tustin is not always accurate the actual date of last frost changes from year to year. Since half of the time in Tustin you get surprised by a frost after January 31 be ready to protect your columbine in the event of one of those late frosts.

USDA Zone Info for Tustin

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 Tustin

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