Hello all, Im still in the process of preparing the garden beds, we have absolutely no top soil, in this particular area, lots of rocks & clay. So I have been layering newspaper,or cardboard or carpet, then sugar cane mulch, today I did another layer on top of that & include rooster pooh, I hope this question doesnt sound too silly , but could I use an old matress as I do the carpet?? Then cover that in mulch??? Also Ive been wrapping my vegies & coffee scraps in newspaper & adding this, to mix of mulch etc, is that ok??