You have to use tap with organics. That is the whole idea also. You are using naturally occurring ingredients and techniques. As much as I love GH, I do not recommend their organics. They are not that good, and are expensive. When it comes to chemicals, they are the best. Kellogg's is the soil manufacturer. It is their raised bed & potting mix blend that is what you need. Do not get garden soil or top soil. Those are amendments for poor loamy soil. It is too rich and dense to be used alone. I have heard 420 soil is top notch also. That is one I would get if you can not get Kellogg's.