Before planting it is a good idea to find your USDA Zone info to determine 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 best time to plant hosta in Seattle should be estimated by reviewing the USDA zone info.

Planting Calendar for Hosta

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

Hosta do well in moderate cold which means that you can get them planted earlier than other plants that might not handle the cold.

The earliest that you can plant hosta in Seattle 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 hosta and expect a good harvest is probably September. You probably don't want to wait any later than that or else your hosta may not have a chance to really do well. You can get started a couple of weeks earlier by starting your hosta indoors.

Last Frost Date

In Seattle 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.

Since the USDA zone info for Seattle is just an average the actual date of last frost changes from year to year. Half of the time in Seattle last frost occurs after March 15 so be sure to be ready to protect your hosta if you have one of those late frosts.

USDA Zone Info for Seattle

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 Seattle

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