Which plant was the first to flower and produce seeds in space?

The first plant to flower and produce seeds in space was Arabidopsis, specifically Arabidopsis thaliana.

The milestone occurred in 1982 aboard the Soviet Salyut 7 space station. The crew grew Arabidopsis plants for about 40 days, long enough for them to complete their life cycle by flowering and producing seeds. This made Arabidopsis the first plant known to reproduce in space.

Arabidopsis thaliana is a small member of the mustard family, Brassicaceae. It is especially useful in research because it has a short generation time, a compact genome, and many easily observed genetic traits. Its genome was fully sequenced in 2000, helping establish it as one of the main model organisms in plant biology.

This achievement is sometimes confused with later experiments involving wheat, zinnias, or other crops and flowers grown aboard spacecraft. Those experiments expanded knowledge about plant growth in microgravity, but they did not precede Arabidopsis's 1982 flowering-and-seeding milestone. Arabidopsis seeds also traveled to the Moon aboard China's Chang'e 4 mission in 2019.