The 'Lucifer' crocosmias look brilliantly red this summer.
It's funny -- the botanical name is crocosmia, which is a little hard to say or to spell, but the common name is even more awkward: montbretia, after a French botanist named de Montbret.
A little used common name that's much easier is coppertips -- these plants often have yellow orange blooms. Or falling stars, which is descriptive and quite beautiful and should be used all the time.
But mostly you have to wrap your tongue around crocosmia or montbretia if you want to talk about these.
Or Lucifer if you have the satanic red ones.