Recently, they made a zinnia bloom in space:
http://www.nasa.gov/image-feature/first-flower-grown-in-space-stations-veggie-facility Turns out this wasn't the first flower to bloom aboard the International Space Station - a sunflower bloomed there in 2012:
http://www.space.com/31687-zinnia-not-first-flower-in-space.html So it wasn't the zinnia, but the sunflower, that was the world's first asternaut!
(Apparently the Russians grew some beans and arabidopsis that flowered in space many years earlier, but no asters as far as I know.)