Predicting Cherry Blossoms

Photo: Judy Miller

Author: Anthony Aiello - The Gayle E. Maloney Director of Horticulture & Curator, Morris Arboretum of the University of Pennsylvania

Ornamental cherries (Prunus) are one of the main reasons that spring is my favorite time of year.  I know that spring has reached its peak when these trees are in full flower. After our hard winter and cold start to spring, you may be wondering if and when the cherry blossoms will arrive.  I can easily answer the ‘if’ question and say definitively that they will flower this spring.  As for the ‘when’ question, that is more complicated, but I can at least provide some background.

Recently the National Park Service has predicted that peak bloom dates for the Yoshino cherries around the Tidal Basin in Washington, D.C will be delayed until sometime around April 11-14th (see D.C. dates).  Similarly, Jason Samenow of the Washington Post has predicted peak dates between April 9-13th.  Either way, this is about one week later than the historic peak of April 4th in Washington.

Now what does that mean for us in Philadelphia? Normally, I would predict that the peak flowering for the Yoshino cherries along Kelly Drive is roughly one week behind that of Washington.  A lot depends on what happens in the next two weeks, but if temperatures remain below or close to normal, we should expect our Yoshino cherries flowers to peak sometime around April 17-20th.  Although this may seem late, last year the peak along Kelly drive was right around April 16th, so we are not far off from last year, which you might remember was another cold winter.

We invite you to start your own search for the first blossoms of the season at Morris Arboretum's Japanese Cherry Blossom Festival on April 11 and 18. Enjoy traditional cultural events such as performances by the Kyo Daiko Drumming Crew, origami workshop for kids, and tours. See the full line-up here.