My daylilies haveorange spots on the undersides of leaves and plants don look good. What should I do?
This is most likely a new disease, found now in at least 20 states and Costa Rica, a fungal rust called what else, daylily rust! (Puccinia hemerocallidis) This is an Asian species, imported and first seen on plants in Georgia in 2000. It can merely cause the characteristic raised rust colored spots on leaf undersides to killing foliage. Some cultivars appear more susceptible than others, with Pardon Me one of the most susceptible. Happy Returns, Stella D’Oro, and Joan Senior are popular moderately susceptible cultivars. Holy Spirit appears among a few others least susceptible. Best control is by not introducing it, so if ordering daylilies or buying them in, some keep them isolated from others for up to 6 months or a season in the north to see if disease develops. If present, cut off infected foliage. Several fungicides for rust appear to control it, but should be rotated among different types every few sprays to prevent resistance. There are many websites on this disease, merely type
