According to one article I read it took a gardener over three years of doing this to banish the pest! Next year we will try spraying Provado in March and April to banish the bug.
Gall midge is a small fly that lays eggs on the developing flower buds. The larvae inside the buds causes abnormal bud development and infested buds fail to open. These buds are shorter and much fatter than normal daylily flower buds. It affects the earlier varieties of Hemerocallis more as they are forming in the egg laying season. It is worth trying the spray provado ultimate bug killer when the flower spikes are emerging.