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.

The USDA zone info for Sammamish can be read to figure out when it's a good idea to plant liatris.

Planting Calendar for Liatris

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

Liatris tend to make it in pretty solid cold which means that you can plant them much earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant liatris in Sammamish 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 liatris and expect a good harvest is probably September. You probably don't want to wait any later than that or else your liatris may not have a chance to fully mature. Starting your liatris indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Sammamish the average date of last frost happens on March 15. It might get as low as 15°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 Sammamish and it will vary from year to year. Since half of the time in Sammamish it frosts late in the year after March 15 be ready to cover your liatris if you have one of those late frosts.

USDA Zone Info for Sammamish

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 Sammamish

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