I grow citronella scented pelargoniums all over the place, if you rub the leaves on your skin, or even make a tea out of the leaves and spray it on your and your pets, it keeps the flies and mozzies away very effectively, smells nice too, lemony. I grow the bushes around the patio and verandas and this keeps them at bay, pennyroyal and mint are also good to grow around your outdoor areas, and smell divine :)
I use DE and a tansy and Wormwood rinse, to keep fleas, flies,mites and mozzies, from bothering my pets, safe and effective. Tansy can also be used a a hair rinse to keep head lice away from kids.