The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Boulder City should be reffered to in order to determine when you can plant doronicum.

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 moderate cold which tells us that you can start planting them earlier than other plants that might not handle the cold.

The earliest that you can plant doronicum in Boulder City 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. If you wait any later than that and your doronicum may not have a chance to really do well. Starting your doronicum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Boulder City. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Boulder City is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Boulder City last frost occurs after February 15 so be sure to be ready to protect your doronicum if you have a late frost.

USDA Zone Info for Boulder City

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 Boulder City

You may be interested in your other planting guides for Boulder City.