Keith's note: Beautiful pictures of flowers in space have been posted by Scott Kelly on Twitter - and they're very popular. Alas, NASA does not post these high resolution images online. There's no mention at Scott Kelly's flickr, JSC's Flickr, etc. But more importantly this "First ever flower grown in space" claim is totally bogus - just ask Google. It has been done more than once - and many years ago. Score another failed tagline for PAO's fact checking folks.
"In 1982, the then Soviet Union's Salyut-7 space station crew grew some Arabidopsis on board. During their 40-day lifecycle, they became the first plants to flower and produce seeds in the zero gravity of space."
Plant growth, development and embryogenesis during Salyut-7 flight, Adv Space Res. 1984;4(10):55-63.
"The seeds sown during the flight germinated, performed growth processes, formed vegetative and generative organs and, judging by the final result, they succeeded in fecundation, embryogenesis and ripening."
Modification of reproductive development in Arabidopsis thaliana under spaceflight conditions, Planta, April 1996, Volume 198, Issue 4, pp 588-594
"Reproductive development in Arabidopsis thaliana (L.) Heynh. cv. Columbia plants was investigated under spaceflight conditions on shuttle mission STS-51. Plants launched just prior to initiation of the reproductive phase developed flowers and siliques during the 10-d flight."
June 17-26 - Diary of a Space Zucchini, Don Pettit (2012)
"Sunflower is going to seed! His blossom is wilted-brown and has a few lopsided packed seeds. This is not quite normal, but then, we are living on the frontier and things are different here. They are not ready now; I wonder if they will be by the time Gardener is with his seed pod?"
"And according to the website NASA Watch, cosmonauts produced flowers several times in the pre-ISS days of spaceflight. It seems that in at least one case, the entire growth process occurred during flight. That was a lettuce plant, but lettuce plants can flower - and according to research published on the subject, it appears the Russian lettuce did."