Thanks, Sue, for replying! Interesting information.
I know that I should plant my daylilies on a mound, but often I don't. I remember having some older daylilies pull themselves down into the soil years ago. This was 15 years ago when I had a clump of NOIDs that someone gave me as a gift. I planted them and they bloomed well and multiplied. I should have divided them, but didn't. I noticed that they were going underground and eventually I lost all of them. At the time, I knew nothing about daylilies and didn't know what to do to save them, so I didn't do anything and they eventually disappeared.
