Hello,I am preparing a new raised vegetable garden bed that will be 6' x 10" with 10" fill. What is the suggested % of fill for a) peat moss; and b) hot compost. (Just started last fall from a spot in Hopkins.) and bags of dirt. We estimate 1.85 cubic yards of dirt needed. I just need some basic / rough portions on peat moss, compost and dirt. Thank you, Mary
Carver County Minnesota
There is no set proportion. Many people use 1/3 soil, 1/3 compost or peat, and 1/3 well rotted manure, but you can use both compost and peat if you want. The peat will change (lower) the soil pH. This is great when using our native soil as it is usually alkaline, but, depending on where the bagged dirt is from, might not be necessary. I wouldn't go over 1/3 with that unless the soil is alkaline. I assume the compost you refer to has finished decomposing. If there are still some bigger chunks, put them at the bottom of your bed.
When you are buying bags of dirt, look for ones labeled "top soil" instead of "black dirt". Black dirt can be anything and there is some nasty stuff out there.
Compost and peat compress after a few months, so you will need to top off the bed after the first season. Annual additions of a few inches of compost (or peat if a soil test shows the pH is high) are recommended.
Your calculation of 1.85 cu yards is correct if you meant to say the bed will be 10 feet wide instead of 10 inches wide.
Here is a little more information on raised beds: