We live in an area with a lot of rocks so after hours of digging to plant some blueberry plants we decided we would plant four blackberry plants and two blueberry bushes in a raised garden bed four ft by 16 ft and about 15 inches tall. My question is about what to use to fill the beds besides soil and compose from our local nursery. We have wood chips, leaves, grass clippings. Could I fill the first five inches with that before getting soil and compost from the local nursery to save money? Any other ideas? We are starting to compost all organic material but only started about a month ago. Thanks for any suggestions.

Blueberries need a acidic pH 4.3 to 5.5 to grow and bare fruit. Blackberries like acidic to neutral between 5.5 and 7.0 pH. So to acidify your soil enough, you need to use peat moss mixed with shredded pine bark to lower the pH enough to work. If you just use compost and soil you will have too high a pH and the nutrients will not be available for the plant to use. Peat moss has a pH of 3.8 to 4.4 and mix with pine bark raises the pH to perfect range for Blueberries. When you mix the two together you will need to fortify it with some time-release nutrients like osmocote 12-12-12. That will last the whole season and next year you replenish the time-release fertilizer.