Before planting it is a good idea to find your USDA Zone info to estimate your garden 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 estimate when to plant doronicum by looking at the USDA zone info for Mercer Island.

Planting Calendar for Doronicum

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

You can plant doronicum a little earlier in the year because they are moderately cold tolerant.

The earliest that you can plant doronicum in Mercer Island 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 Mercer Island the average date of last frost happens on March 15. In the coldest months of winter you can expect an average low temperature of 15°F.

Always keep in mind that USDA zone info for Mercer Island is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Mercer Island last frost occurs after March 15 so be sure to be ready to cover your doronicum if you have a surprise late frost.

USDA Zone Info for Mercer Island

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Mercer Island

You may be interested in your other planting guides for Mercer Island.