One of the first steps you take when you are making a decision about 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 first chance to plant centaurea in Riverbank can be estimated by reviewing the USDA zone info.

Planting Calendar for Centaurea

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

Since centaurea are moderately cold tolerant you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant centaurea 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 centaurea and expect a good harvest is probably October. You probably don't want to wait any later than that or else your centaurea may not have a chance to fully mature. You can get started a few weeks earlier by starting your centaurea indoors.

Last Frost Date

In Riverbank the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 25°F.

It's important to remember that USDA zone info for Riverbank is an average and the actual date of last frost is different every year. Since half of the time in Riverbank there is a last frost after February 15 be ready to cover your centaurea if you have a late frost.

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.