The University of Washington encourages the public to savor the renowned Quad cherry blossoms on campus this spring. The 29 cherry trees situated in the University of Washington Quad typically attract significant audiences on campus, reaching peak bloom during the third week of March, and this year appears to adhere to that schedule. 

Higher temperatures and moderate climate conditions determine when the cherry trees commence blooming and when they attain peak bloom. The UW’s Bloom Watch is frequently updated to indicate the current blooming phases, including anticipated peak bloom times.

The UW’s notable Yoshino cherry trees generally bloom between March and April, yet predicting the exact dates for future visitors presents an annual difficulty. To enhance their forecasts, a research team from UW is utilizing historical weather records dating back to 1966 alongside observational data collected by students to ascertain the timing of peak bloom — while also examining how a warming climate influences that date. Once the blossoms reach peak bloom — defined as at least 70% of the flowers having opened — lower temperatures, dry conditions, and minimal wind will help the blossoms persist on the trees longer. 

“Our research indicated that in Seattle, due to our winters being relatively mild and warm, there has been a noticeable delay in bloom timing over the last sixty years,” remarked Autumn Maust, a doctoral candidate at UW’s School of Environmental and Forest Sciences. “The bloom period is shifting to happen slightly later.”

This shift occurs because cherry trees must accumulate both chilling and warming units — which are gained during spring’s cooler and warmer days — to realize a threshold that prompts them through their blooming phases. According to Maust, milder winters imply it takes a longer duration to gather the necessary chilling units. 

Numerous varieties of flowering cherry and plum trees populate the Seattle region, with its blooms for certain species observable from early February until May. Bloom colors span from white to light rose and deep pink, while cherry trees — in contrast to plums — exhibit distinct horizontal line patterns on their bark known as lenticels. These features enable the trees to “exhale” or release carbon dioxide and moisture.

However, there’s no need to postpone your visit to campus until peak bloom, as the season is in progress. The UW manages a visitor’s webpage dedicated to providing updates on bloom status, in addition to information on travel, events, and facilities. The Quad cherry blossoms also maintain their own social media profiles on Instagram and X. Cherry tree admirers who are unable to visit can stay informed via UW Video’s live webcam overlooking the Quad, a virtual tour with images from campus and tweets from @uwcherryblossom. 

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For additional details or to arrange an interview, kindly contact Dana Robinson Slote: [email protected] or 206.457.6058