A cubic yard = 27 cu. ft. (3 x 3 x 3)
A 10′ x’ 10′ garden (100 sq ft.) if you cover it 1/4′ high (3 inches) = 25 cu ft. (approximately equal to a cu. foot.)
So for 100 sq. ft. you would need a minimum of 1 cubic yard of compost and mulch for a 3 inch coverage.
St. Louis Composting has a nice calculator which allows you to put in your dimensions and it will show you the cubic yards you need to buy. (click here)
Another option I suggested with one school is to put 6″ to 9″ of Super Soil down over the existing soil after killing the grass and weeds. I have tried this on one part of my garden and it worked great.
COMPARISON of COST
As you see below, if you only need a small amount of mulch or compost, the best deal is Home Depot, but it you need five or more cubic yards, it would be better to have St. Louis Composting deliver the mulch to your location. Of course you need to figure in your time and car expense to drive to Home Depot and pickup the mulch.
|$ for 27 sq. ft.||Delivery Cost||Total Cost|
|St. Louis Composting||$18||$66||$84|