One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when it's a good idea to plant columbine in Holtville by referring to the USDA zone info.

Planting Calendar for Columbine

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

Since columbine do well in moderate cold you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant columbine in Holtville 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. You probably don't want to wait any later than that or else your columbine may not have a chance to really do well. If you are starting your columbine indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Holtville the average date of last frost happens on January 31. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Holtville is not always accurate the actual date of last frost is different every year. Half of the time in Holtville you get surprised by a frost after January 31 so just be sure to be ready to protect your columbine in the event of a surprise late frost.

USDA Zone Info for Holtville

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 Holtville

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