How many yards of dirt will I need to fill my yard with beds. The yard is 50 by 30 and beds will be 3 ft wide and 6 inches deep?
That is a lot of yards to fill your yard. We are missing some critical information to determine the number you are looking for. How long should each bed be, and how far apart would you like them?
We can still determine our best guess, with the information you provided. First we will start with the backyard itself, at 50′ x 30′, you have an area of 1500 square feet. A yard of dirt is 3′ x 3′ x 3′, or 27 cubic feet, and if you are spreading it 6″ deep, you would be able to spread 27 cubic feet across 54 square feet. That said, you would need almost 28 yards of dirt to cover the whole 1500 square ft yard with 6″ of dirt.
If your beds were 3′ wide, which is the only measurement you provided, that may indicate that they are square, 3′ x 3′, if you wanted them a minimum of 6″ apart, the most you could fit in the yard is 8 down the 30′ side, which would be 24′ of beds, and 4′ of combined gaps between them, and down the 50′ side you could have 14, which would give you 42′ of beds, and 7′ of gaps. So now you have a total of 112 beds, and you would get 6 out of every yard of dirt if they were 3′ x 3′ x 6″ so that would take 18.6 yards of dirt.
If you just wanted to surround your yard with a 3′ wide bed, you would need 8.2 yards of dirt, to make a box shaped bed, that has a 50′ x 30′ outer perimeter, and 44′ x 24′ inner perimeter.
If you still don’t know how long the beds will be, just keep in mind that you will get 18 linear feet of beds per yard, if they are 6″ deep, and 3′ wide. So you could have 3 6′ x 3′ beds per yard of dirt.
Yet even another way to illustrate the same calculation would be 2.77 yards required for every bed that is 50′ long, 3′ wide, and 6″ deep.