I think or actually I have proven to myself they both make a difference in hydro, water and coco coir, but I use them at about 1/4 the recommended strength in early flower and about 1/2 strength in later flower up to a week before harvest. I think roots have to work harder in soil than they do in hydro so that boosts the terp production. Now that I have the brix levels up in hydro grows I will test some in soil this summer and see how it looks and smokes