One of the first steps you take when you are determining 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.

You can figure out when it's possible to plant bidens in Santa Rosa by using the USDA zone info.

Planting Calendar for Bidens

Frost tolerance for bidens:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since bidens do not do well in cold weather it's necessary to wait until after the last frost before you can plant them.

The earliest that you can plant bidens in Santa Rosa is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant bidens and expect a good harvest is probably September. You probably don't want to wait any later than that or else your bidens may not have a chance to really do well. Starting your bidens indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Santa Rosa. In the coldest months of winter you can expect an average low temperature of 25°F.

Since the USDA zone info for Santa Rosa is just an average the actual date of last frost changes from year to year. Half of the time in Santa Rosa last frost occurs after February 15 so make sure that you are prepared to protect your bidens if you have a surprise late frost.

USDA Zone Info for Santa Rosa

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 Santa Rosa

You may be interested in your other planting guides for Santa Rosa.