Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant columbine in Mill Valley should be estimated by reviewing 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.

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

The earliest that you can plant columbine in Mill Valley 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 fully mature. 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 Mill Valley. It might get as low as 30°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Mill Valley and it changes from year to year. Since half of the time in Mill Valley it frosts late in the year after January 31 be ready to cover your columbine if you have a surprise late frost.

USDA Zone Info for Mill Valley

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 Mill Valley

You may be interested in your other planting guides for Mill Valley.