One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

It's possible to determine when it's possible to plant columbine by using the USDA zone info for Pasadena.

Planting Calendar for Columbine

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

Columbine can survive in some cold which means that you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant columbine in Pasadena 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. If you wait any later than that and your columbine may not have a chance to really do well. Starting your columbine indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Pasadena. You can expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Pasadena is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Pasadena you get surprised by a frost after February 15 so always be ready to cover your columbine if you have one of those late frosts.

USDA Zone Info for Pasadena

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 Pasadena

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