Q: What’s the most important ingredient in your garden? A: Your soil! The folks at Seattle Tilth, in my training and in the Maritime NW Garden Guide, have always emphasized the importance of good soil. They refer to it as a “living bank”. What I took away from that (and I am oversimplifying once again) is that you have to make deposits, by adding organic matter (humus) and nutrients (nitrogen, phosphorous and potassium) to give plants what they need to feed and grow. Since different plants feed heavily on different nutrients, fertilizing (and rotating crops) helps keep your living bank from running empty. I make deposits to my living bank…