For the darkest night a bit of flash can make many patterns more efficient. Water movement is the key. In the summer coastal points and reefs below the surface are the places to seek. Fish in the 'back water' meaning behind the reef that you'll often see below points on the shore. If the current goes right, fish on the right side and vice versa.
Fish are more shy than in the spring.
They will nibble the flies and follow without taking. They offer excellent sport, and drilling a large trout in the dark night can really get your heart pounding. Summer is the skilled and patient fisherman's season. November Autumn is ideal for catching top condition fish, mornings, days and evenings. If the fish do not react to these small flies a good wildcard can be to switch to a huge, colorful fly like a large Mickey Finn.