One of the first steps you take when you are determining 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 referring to the USDA zone info for Riverbank it's possible to figure out when it's possible to plant columbine.

Planting Calendar for Columbine

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

Since columbine are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant columbine in Riverbank 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 really do well. You can get started a few weeks earlier by starting your columbine indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Riverbank. It might get as low as 25°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Riverbank and it will vary from year to year. Half of the time in Riverbank last frost occurs after February 15 so always be ready to cover your columbine if you have one of those late frosts.

USDA Zone Info for Riverbank

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Riverbank

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