It depends....did you use new fresh sawdust fresh from the saw or the old black sawdust that has been out in the elements 6 or 7 years until it has turned to the texture of black crumbly dirt? I have some seriously compacted rocky soil at my property and it has had to be amended and reworked before it would grow anything....i came up with a mix of one third black sawdust one third black soil that used to be rabbit manure about 10 years ago and the last third is half peat moss and half sand....been doing this awhile and so far haven't had much of a problem except that it's HARD WORK to dig down through all that clay and rock to create a base for any kind of raised bed....
