I grow Daylilies in Liverpool, England, and I became aware of the midges just last year, although they have certainly been present longer without me taking much notice of the damage, so I have been removing affected buds and killing the larvae by pouring boiling water over them. I still get a good display from the affected plants, but I will avoid early varieties in future.
Two plants in particular have been unaffected so far. One is the species lilioasphodelus, which is very early. and the other is High Tor, which is 5.5 feet = 165cm. I have a theory that the midges avoid very tall plants, in the same way that carrot flies never fly above 2 feet, but it is only a theory.
