One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of estimating when it's the best time to plant doronicum is to refer to the USDA zone info for Hillsboro.

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 a little bit of cold which means that you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant doronicum in Hillsboro 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. You probably don't want to wait any later than that or else 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 few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Hillsboro. It might get as low as -10°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Hillsboro and it will vary from year to year. Since half of the time in Hillsboro it frosts late in the year after April 15 be ready to cover your doronicum in the event of one of those late frosts.

USDA Zone Info for Hillsboro

Here is the info for USDA Zone 6a.

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

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Hillsboro

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