I never use dish detergent when making sprays; even though it is often recommended in books, magazines, and TV shows, it is NOT organic, and they all differ, so some may be especially damaging to plants, and some plants may be especially sensitive, as well. Why take a chance? As a spreader/sticker I use ThermX 70 - a yucca based liquid that only requires 1/2 tsp/gal. of spray. A quart of this lasts me several years.
I make a spray using garlic, hot peppers, rosemary, and coriander seeds - all things I have seen in organic sprays, so I figure why not make my own. No exact recipe - about 2 cloves garlic, 3-4 Thai peppers, a tsp of coriander seeds, and about a 6 in. sprig of rosemary, stripped. All this gets blended with a cup of water, then strained, and used with a gal. of spray. Works great as a prophylactic, though something stronger may be needed to get rid of something already established.