Im having a little trouble figuring out the right amount of stone to get. Obviously I know how to calculate mulch but this rock is giving me a little trouble. I am going to be using river rock 1-3" size pieces. My total square footage for several beds total 465 sq ft. Im coming up with 2.75 yards and I think ordering 3 is safe. I know you order stone in tons but do you use the "yards calculation" method? I got my amount by using 2" as the depth. Is that too shallow and I should use 3"? These are like golfball sized stones for the most part. Any help would be appreciated. Im kind of leaning towards getting 4 yards but don't want too much leftover because you can't just throw it and spread out the extra like mulch.