Grab your camera: UW cherry blossoms to reach peak bloom this week

Seattle’s most beloved sign of spring is just days away.

Researchers predict the University of Washington’s (UW) famous cherry blossoms will reach peak bloom on March 20, according to a post by UW News.

The 29 pink trees reach peak bloom when 70% of the blossoms have opened, but the week before and after are still great times to visit, UW News noted.

Cherry blossom trees are a true indicator of spring, as they accumulate chilling units closer to winter and heating units closer to spring.

“The buds need to accumulate a specific amount of chilling units before they can start accumulating the heating units,” Marlee Theil, a UW doctoral student of Environmental and Forest Sciences, stated in UW News’ post. “When it is not as cold, the chilling units accumulate much slower, so it takes them longer to wake up from dormancy, which is very counterintuitive.”

A UW team studied the trees for patterns to put together a temperature model to predict future blooms.

“Our objective in the study was to detect any patterns in shifts of bloom time ranging back from 1966, which is the first record we have of the cherry trees on campus, up until the present day,” Autumn Maust, a recent doctoral graduate from the UW School of Environmental and Forest Sciences, explained in the video below.

Climate affects cherry blossom timing

Researchers found that bloom time has shifted later over the past six decades because Seattle’s winters have been so mild.

“With the climate warming more rapidly in the spring, I expected to see the flowers blooming earlier,” Maust stated. “But as we dove into the literature and examined the data, we saw a delay in bloom, as a result of winter warming in Seattle.”

Historically, peak bloom has fallen between March 12 and April 3, with an average date of March 23, according to UW News. The iconic cherry blossom trees were planted in the Washington Park Arboretum in 1936 and then moved to UW in 1962.

Visitors can find them in UW’s quad, an open space in the middle of the campus.

For more information on the best way to travel to the campus and to see a live cam to gauge optimal blossom viewing, visit UW’s website.

Follow Julia Dallas on X. Read her stories here. Submit news tips here.