Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant doronicum in Sonora should be determined by using the USDA zone info.

Planting Calendar for Doronicum

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

Doronicum do well in mild cold which tells us that you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant doronicum in Sonora 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 doronicum and expect a good harvest is probably October. You probably don't want to wait any later than that or else your doronicum may not have a chance to fully mature. If you are starting your doronicum indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Sonora. It might get as low as 20°F during the coldest months of winter.

Since the USDA zone info for Sonora may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Sonora last frost occurs after February 15 be ready to cover your doronicum in the event of a late frost.

USDA Zone Info for Sonora

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Sonora

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