I've been using a free "natural liquid fertilizer" in my garden this year, and things are growing great -- a little late because of the the weather, but great just the same. But I think the stuff is rather deficient in phosphorus. I have a 50 pound bucket of triple superphosphate in my garage that I bought a long time ago (0-45-0). How much should I use to sidedress my okra, beans, and tomatoes? I don't want to burn them or drive away too many of the earthworms. Just a handful per 20 foot row sound OK?
Is 0-45-0 soluble in water so I could just mix it a little in my sprinkling can?
Bob