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.

You will be able to figure out when it's the best time to plant doronicum by using the USDA zone info for Rolla.

Planting Calendar for Doronicum

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

Doronicum do ok in mild cold which tells us that you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant doronicum in Rolla is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant doronicum and expect a good harvest is probably September. Any later than that and your doronicum may not have a chance to really do well. You can get started a couple of weeks earlier by starting your doronicum indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Rolla. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Rolla may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Rolla it frosts late in the year after April 15 be ready to protect your doronicum if you have one of those late frosts.

USDA Zone Info for Rolla

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Rolla

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