What plant hardiness zone is Martha Lake

Martha Lake is located at Snohomish County, Washington (WA), USA.

Plant hardiness zone (winter frost zone or gardening zone) for Martha Lake is 8b by the USDA scale.

Coldest zone's winter temperature is +15 … +20 °F.

Plants of 8b USDA hardiness zone suitable for outdoor gardening and growing in this winter frost zone 8b USDA.

Martha Lake, Washington @ wikipedia.