Mystery of the Space Cherry: Cherry Seeds Go to Space, Bloom Twice as Fast

Cherry blossom

Botanists are baffled after a cherry seed, which traveled to space and back, has bloomed at least five years ahead of schedule. Normally cherry blossoms flower 10 years after a cherry tree is planted and first sprouts. The cherry seed that astronaut Koichi Wakata, now commander of the International Space Station, brought to space five years ago has bloomed in half the time.

The pit was special — one of about 265 produced by the fruit of the famous 1,250-year-old "Chujohimeseigan-zakura” cherry tree in the Ganjoji temple in Gifu that were sent to space, according to the Asahi Shimbum.

In 2008, the Tokyo-based Japan Manned Space Systems Corp. sent them to the International Space Station. Wakata brought the stones home in July 2009.

Temple Ganjoji Japan
Temple Ganjoji Japan

Attempts to grow seeds from the Chujohimeseigan-zakura are usually unsuccessful, but cherry tree master botanist Takao Yoshimura, 78, did manage to make a few of the space seeds grow.

One is now a 13-foot tree. This year it produced about 10 buds, which all bloomed by April 4.

Yoshimura confirmed it usually takes a decade or longer for a cherry tree to grow flowers, but all the space pits that sprouted are flowering early.

What's even more strange is that these flowers usually have 30 petals. The space blooms have five petals.

There is a theoretical possibility that the cosmic environment has had a certain impact on agents in the seeds that control budding and the growth process, but we have absolutely no answer as to why the trees have come into bloom so fast,” said Kaori Tomita, 56, a botanist and lecturer at University of Tsukuba.

Yoshimura posits that the seed is a glimpse into the past. The Chujohimeseigan-zakura is derived from a 7th century cherry blossom.

“As it is grown from a seed, the young plant might have reverted back to have the characteristics of original yamazakura species,” Yoshimura said.