One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of getting a good idea when it's a good idea to plant doronicum is to examine the USDA zone info for Umatilla.

Planting Calendar for Doronicum

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

Doronicum tend to make it in moderate cold which means that you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant doronicum in Umatilla 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. If you wait any later than that and your doronicum may not have a chance to grow to maturity. 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

In Umatilla the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 5°F.

Since the USDA zone info for Umatilla is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Umatilla there is a last frost after April 15 be ready to cover your doronicum in the event of a late frost.

USDA Zone Info for Umatilla

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Umatilla

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