I also have gypsum which I really like when I have poorly drained soils. This will help loosen clay soil over a slow period of time. I've put about a handful of that in this mixture. I also have lime which helps lower the PH if I have a real high acidic soil and I am going to work a little bit of that in as well. This is a pulverized lime so it is a bit faster acting. Finally we are going to put a little bit of triple super phosphate. Phosphate helps stimulate root development and helps improve the vigor of the plant and fight against some disease; so put about a tablespoon of that. Then I am just going to take my shovel and work that in there and combine it all and if I have some clumps, I actually get my hands in there, break up these little clusters of any kind of hard clump balls because you want it to be as light and fluffy as possible so the roots can root in there easily enough. I just kind of mix it like you are mixing a cake. There you have it a nice fluffy mix to plant just about anything. It is a good general mix for just about any type of perennial.