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.

In Santa Rosa you can determine when you can plant diascia by referring to the USDA zone info.

Planting Calendar for Diascia

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

Diascia do well in moderate cold which means that you can plant them a little bit earlier than other plants that might not handle the cold.

The earliest that you can plant diascia in Santa Rosa 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 diascia and expect a good harvest is probably October. If you wait any later than that and your diascia may not have a chance to grow to maturity. Starting your diascia indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on February 15 in Santa Rosa. You can expect an average low temperature of 25°F in the coldest months of winter.

Remember that USDA zone info for Santa Rosa is just an average and the actual date of last frost will vary from year to year. Half of the time in Santa Rosa there is a last frost after February 15 so be sure to be ready to cover your diascia in the event of 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.