I use my common sense, what little science I know, things I learn, (specially online), and the old folks' wisdom in my gardening. My main focus is to do my gardening while keeping the natural environment as intact as possible. That means a lot less weeding, no chemical fertilizers, no chemical pesticides or
weedicides, less exotic plants, friendly habitat for local wildlife in my garden, and so on. It's not an easy task growing plants organically, specially with the hybrid seeds that have invaded our local market. I use local varieties whenever I can, but it's not easy as those are on the decline. It's too bad there's no tradition of heirloom seeds over here.
I invite you to visit my wildlife photography blog, Wild Sri Lanka too.