I read somewhere an article by a guy who had observed that his daffodils which grew in the full sun, got narcissus fly, but ones which were a lot in the shade, didn't. And so far I have never had any bother with my daffodils etc, as they are in a part of the garden which doesn't get much sun. It doesn't seem to affect their flowering. The Hypeastrums have been fine so far, for years now also. Don't know if that would help. Ina Crossley Auckland, New Zealand