Hanami on the Hill: Cherry Blossom Season on U.S. Capitol Grounds

Every March more than a million people visit our nation's capital to enjoy the splendor of the cherry blossoms. While most gather at the Tidal Basin to see the grandest collection of trees, the city is filled with blooming cherries and many of the finest examples are found on the grounds of the U.S. Capitol and the Library of Congress. Some of these trees are as old as the ones found around the Tidal Basin and have become an iconic feature of Capitol Grounds and a beloved tradition for those who visit to witness their fleeting beauty.

At the Architect of the Capitol (AOC) cherry trees are maintained by a team of arborists from the Capitol Grounds and Arboretum jurisdiction. The team works year-round to preserve these historical assets that embellish the landscape with their majestic presence.

A Rare Gift

Many who come to Washington, D.C. to see the cherry blossoms (a practice which parallels the Japanese ritual of Hanami, or "flower viewing") will know that the trees found around the Tidal Basin and East Potomac Park were originally a gift of friendship made in 1912 from the nation of Japan. It is less commonly known that a handful of the original 3,020 gifted trees were transplanted to other locations around the city in 1922, including the grounds at the U.S. Capitol and the Library of Congress.

Capitol Square is now home to several groves of Yoshino cherries (one of which contains a tree that was gifted in 1912) and about half a dozen other varieties of flowering cherry trees. The Senate Parks are home to even more cherry tree varieties, including many examples of Yoshino, Kanzan, Higan and Okame cultivars.

Kanzan, Higan and Okame cherry trees blossom near the U.S. Capitol Building.

Yoshino cherries bloom early, their pink buds opening to reveal nearly translucent pale petals. They comprise the vast majority of cherry trees found around the Tidal Basin and East Potomac Park. Kanzan cherries have large, cotton candy-colored blossoms which take a while to arrive but are very common around Washington, D.C. Higan cherries are a weeping variety and are unmistakable for their dramatic poses. Okame cherries bloom the earliest, changing from fuchsia to hot pink as they emerge. Together, these blossoms paint the city landscape with beautiful blooms every spring.

Caring for Our Elders

At daybreak on a muggy morning last July, our team of arborists discovered an unwelcome but not unusual scene in the grove of Yoshino cherries located just southwest of the Capitol. It was several weeks since the last rainfall, and one of the trees had lost its whole top, collapsed under the stress of drought and the weight of its own foliage. These dramatic structural failures are a natural part of the life cycle of cherry trees, although weather fluctuations may be causing them to occur in younger trees. The broken tree is almost 70 years old, while its elder neighbor turns 113 this year (if you consider arrival from Japan as its birthday). The elder tree has lost its fair share of limbs over the years as well and would not be standing today without the support of a pair of steel props that were installed over a decade ago. The failure of the younger tree, which may never recover, was a stark reminder that these trees live much longer with proper support.

In Japan, some old cherry trees are considered to be the residence of a deity or are dedicated to the memory of a long dead emperor. Such trees are given the same treatment as an aging senior: thorough preventative care and physical support before a fall occurs. In the U.S., it is not uncommon to prop, cable or brace important trees, but it is typically done minimally and only when failure appears imminent. The Japanese approach does not try to hide structural supports or wait until they are absolutely necessary. There is pride in caring for an aging tree, and cutting a tree down to start over is considered a last resort. It is with this philosophy of arboriculture that some cherry trees have been sustained for over a thousand years in Japan.

More views of the Yoshino cherry tree located just southwest of the U.S. Capitol and its new wooden braces.

With this goal of longevity, and an interest in honoring the Japanese origin of these trees, we solicited the help of Master Gardener Kurato Fujimoto, who spends most of his time caring for the aging trees at Kenroku-en, one of Japan’s great walking gardens. Mr. Fujimoto taught Capitol Grounds arborists how to best preserve the historic cherry trees on campus using a Japanese horticultural practice where wooden braces called "hoozue" are placed to gently hold heavy branches and support the trees.

Preserving These Historic Living Assets

The process begins with evaluation of the cherry trees, determining which limbs are to be supported and the disposition and size of the hoozue needed. Measurements are taken and poles are ordered, some as long as 30 feet to support the highest limbs in the tree. A hoozue is built by cutting the bottom off a pole and using it as a crosspiece, drilling a hole to fit onto the top and form an elongated "T."

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T-shaped hoozue installed with care by the AOC's Capitol Grounds and Arboretum jurisdiction.

Soil is loosened with compressed air and removed with hand tools to avoid damaging roots, and the hoozue is lifted into place. It is then tied to the tree with palm fiber rope and padding which protects the bark while allowing moisture to evaporate so as not to encourage rot. Existing steel props are replaced with these more robust timber props that will not damage the tree. Many additional hoozue are added to support overextended limbs, allowing the tree to focus resources on production of photosynthetic material, rather than structurally reinforcing itself with more wood.

On the eve of the 2025 cherry blossom season, arborists from the AOC's Capitol Grounds and Arboretum team applied their new learnings to install 19 hoozue on a few trees located near the U.S. Capitol and the Library of Congress Thomas Jefferson Building. On the final day of installation on Capitol Square, the tree's earliest buds began to burst open as if to say, "thank you."

Two cherry trees near the Library of Congress Thomas Jefferson Building now have these special wooden braces called "hoozue" installed for support.

Preservation of the cherry trees on U.S. Capitol Grounds serves as a powerful reminder of the importance of protecting our historic living assets. The trees, some gifted by Japan over a century ago, have become symbols of friendship, resilience and the beauty of cultural exchange. By safeguarding them, we honor not only the legacy of those who planted them but also our responsibility to future generations.