Q. I was thinking of using brown cardboard from fridge and stove boxes as a mulching in the bottoms of the raised beds to prevent weeds coming up into the beds, so I don’t have to dig, rake and work that soil so much prior to installing the soils the beds. Is there any reason not to do this?
I’m digging a foundation for another building and have that dirt to move, I thought it would be good in the raised beds with some additives, like peat moss, sand and manure and straw in the lower layers. etc..
How about some used linoleum, or carpeting on the bottom side of the beds? I’m making the beds 16 inches deep (so I don’t have to bend down so much as I get older.)
A. One important factor to consider in choosing whether or NOT to put ANYTHING under your Grow-Boxes is the drainage implications. If the material stops or even slows the natural drainage you may substantially hurt your crop and even kill it with a build-up of water and/or salts.
Another factor to consider before putting anything under your Grow-Boxes is that plant roots will – if the soil is available to them – travel down into the natural soil and pick up additional plant nutrients and minerals that may be valuable for humans and animals that may not be essential for healthy plant growth.
Container height only needs to be 8″. Anything more than that 1) increases the cost of building the container, 2) increases the cost of filling the container, 3) increases the cost of watering, and 4) may reduce the effectiveness of the fertilizer somewhat.
We recommend placing the boxes directly on clean soil that has been leveled. Then apply the Pre-Plant Mix, and then fill with clean inert “soil mix” materials, as well as the Weekly Feed and Pre-Plant Mixes.
The soil mix materials should NOT include dirt or manure – for several reasons:
1) Dirt is HEAVY and can push out the sides of the box.
2) Dirt often does not drain vell,
3) Dirt becomes hard and difficult to work with,
4) Dirt and manure very often contain millions of weed seeds,
5) Dirt and manure often include unwelcome bugs and/or diseases.
Jim Kennard
