9:45 AM | Cherry blossoms in DC should peak around April 9th or so

[Cherry blossoms near the FDR Memorial in DC]

Discussion

Overview

February was significantly colder-than-normal in the DC metro region and March is running slightly below normal for the half of the month. Despite a couple of mild days to start this new week, a colder-than-normal pattern will return on Wednesday throughout the I-95 corridor and it is likely to continue right through March and into the first week or so of April. Given the winter conditions so far in the DC metro region and the expectation of primarily colder-than-normal conditions for the next few weeks, I believe it is likely that the cherry blossoms will reach a peak later than normal this year – perhaps right around April 9th or 10th – give or take a couple of days. Peak is defined here as the day when 70% of the cherry blossoms are open and typically the bloom period is several days depending on weather conditions.

Temperatures and the peak blossom date

Historically, bloom dates have shown a strong relationship with March temperatures. When temperatures are warmer than normal in March, the blossoms tend to peak early. Conversely, when March is cold, the blossoms peak late. Bloom dates have almost always been later than average when March temperatures have been at least two degrees below average and that is very likely to be the case this year in DC. Once April begins, the buds should be working through their stages of development. The weather will play a key role into how fast they mature. Warm, sunny days and mild nights will accelerate the process whereas chilly, cloudy days and cold nights will slow it down.

Blossom peak records have been maintained by the National Park Service since 1921. The average cherry blossom peak bloom date in the DC metro region from 1992 through 2013 is March 31st. The earliest bloom date on record was March 15th (1990) and the latest was April 18th (1958) according to the National Park Service. The last time the blossoms peaked early was in 2012 when it took place around March 20th.

Some of the history behind the cherry trees

When the cherry trees first arrived in Washington, D.C., on January 6, 1910, they were unfortunately bearing more than just goodwill. The Department of Agriculture discovered the trees were infested with insects and parasitic worms. On January 28, 1910, President William Taft regretfully gave his assent to destroy the trees, and most were incinerated in heaps resembling giant funeral pyres.

When the second shipment of 3,020 cherry trees, composed of a dozen varieties gifted by Tokyo, reached the capital in March 1912, they were in perfect condition. On March 27, 1912, in a simple ceremony with little fanfare and no photographers, the first lady and the Japanese ambassador’s wife dug their spades into the ground to begin planting the first two trees, which still stand today along the northwest wall of the Tidal Basin. Planting continued for the rest of the decade, and the flowering trees quickly became such a beloved Washington institution that the selection of the Tidal Basin as the location for the new Jefferson Memorial led to howls of public protests from those fearing the mass removal of the trees. Flamboyant newspaper editor Eleanor “Cissy” Patterson, who took daily walks with her poodles under the canopy of the cherry trees, led the grassroots opposition, pledging in the Washington Herald to “defy workmen to so much as break a twig.” The Japanese cherry blossoms have now endured for a century in the nation’s capital, and there are more than 3,750 trees.