Best soil mix for raised beds?

Asked April 1, 2017, 10:29 AM EDT

Planning to build three 4 X 12 by 1-foot raised beds. Since I will have to buy soil and mulch from commercial sources, is there anything I should look for that will provide a growing medium that will stay productive and healthy over time?

Marion County Oregon

1 Response

Thanks for contacting Ask an Expert about filling your new raised beds.

Most bulk producers these days have one or two mixes that are made especially for the raised beds, combining organic matter/compost with soil or other drainage material. Check out local sources to find a mix that looks uniform and smells good (not sour). Check it again before it is piled in your driveway.

When filling your beds, mix some of the new material with the native soil below. This provides a transition zone that allows water to drain more easily. Then fill your boxes the rest of the way.

Each season, mix in additional raised bed mix or compost to “top up” the boxes. As the organic matter in the mix decomposes naturally, the soil level drops.

Don’t forget to establish a good fertilizing program for your new plants, and have a great summer.