At that garden center you should be able to find a wide range of potting mixes. This is an example of a few. This is a light mix which has very fine peat and perlite. This would probably not make a very good mix for a cactus, this is a regular annual mix that we use here a lot. It's got a little bit of bark, some chunkier pieces of perlite and then the peat. Then we have an even chunkier mix that has a lot more bark, same thing, the perlite and the peat, this we use for perennials. So, you want something that's going to have really good drainage with our cactus so we're going to make our own mix. We're just going to take a regular potting mix and we're going to take one part, we'll take out some of the big chunks, we'll just put one part there. Then we're going to take this sand that I have here, it will be about two parts sand and now we're just going to mix it. This soil should have very good drainage because all of the sand but yet it has a little bit of the peat to hold onto some water so it's available to the plant. Let's see, we've got a nice mix here, it's just perfect for a cactus or a succulent.