This came up in middle August, apparently from a bulb, but has no leaves discernible. Is it some lovely pink member of the day lily family?
Looks like Lycoris squamigera .See.... http://images.google.com/imgres?img...microsoft:en-gb:IE-SearchBox&rlz=1I7SUNA&sa=N
Thanks - you are right. Also called the Resurrection Lily and Surprise Lily because its leaves die away - then weeks later up pops this 3-foot set of trumpet blooms! Also found that it's actually not a lily but an amaryllis. We must have planted it years ago (a gift from a relative, no doubt) and forgotten about it.