Has Green Lake Had Its Last Freeze Of The Season?

March 23, 2017 1:12pm

Narcissus ‘Geranium’, Muscari ‘Valerie Finnis’ and a species tulip. Image: Erica Grivas

Editor’s note: With spring upon us, we asked our expert contributors Dustin Guy, a meteorologist, and Erica Grivas, our garden writer, to weigh in on kicking off the Green Lake garden season. Today is the first of the two part series about when to start planting your garden. More specifically, has Green Lake had the last freeze for this season? (Please, let it be so!) The last frost is a time that often signals its safe to start planting. Stay tuned tomorrow for Erica’s post about what to plant. Happy gardening Greenlakers! 

Last winter was more than a bit of an aberration from the typical growing season in Seattle. In 2016, the last freeze was recorded on January 9th and it didn’t freeze again until December 6th. That’s an incredible freeze-free period of 331 days and a major departure from the long term average of 251 days. As you can probably guess, we’ve been brought back closer to reality given the snow events and extended periods of hard freezes we had this past winter. The good news, at least if you are an avid gardener in the city of Seattle, is that we have passed the date of what is typically the last freeze … March 12th. Thanks to the “urban heat island effect” of the city, our proximity to water, and, yes, a changing climate, Green Lake and much of Seattle have a longer frost-free season that outlying communities in nearly every direction on the compass.

Here are some stats on the first and last freezes in Seattle from records dating back to the 1890s. The earliest first freeze of the fall/winter season occured on October 16, 1946. The latest first freeze of the fall/winter season was January 10, 1935. The earliest last freeze of the fall/winter season was January 2, 1946. And the latest last freeze of the season was May (!) 1 of 1951 and 1954. The first half of the 1950s must have been a brutal period for gardeners in Seattle. From 1950 to 1956, the last freeze never occurred before mid April. And that should make this spring feel comparatively balmy!