One of the first steps you take when you are figuring out your gardening schedule is find your 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.

The USDA zone info for Spokane can be reffered to in order to estimate when to plant achillea.

Planting Calendar for Achillea

Frost tolerance for achillea:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Achillea are very cold tolerant which means that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant achillea in Spokane 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 achillea and expect a good harvest is probably September. You probably don't want to wait any later than that or else your achillea may not have a chance to fully mature. You can get started a little bit earlier by starting your achillea indoors.

Last Frost Date

The average date of last frost is April 15 in Spokane. It might get as low as -5°F during the coldest months of winter.

It's important to remember that USDA zone info for Spokane is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Spokane you get a frost after April 15 so just be sure to be ready to cover your achillea in the event of a surprise late frost.

USDA Zone Info for Spokane

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 Spokane

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