Clean cardboard (no tape, no staples) is a great source of for mulching.
Below are some pictures of the cardboard mulching around native plants that were planted in McKinley Square hillside in San Francisco.
The need for the cardboard mulching is to prevent invasive weeds from blocking out sunlight for the young native plants.
Such invasive plants include Oxalis, and Foxtail weeds, Oxalis, although not a hazard to dogs like fox Foxtail, contributes to the success of the Foxtail, as Oxalis is strong in rainy season, and Foxtail follows once the Oxalis goes dormant. Its a 1-2 punch against native plants.
The native plants we are protecting with this cardboard mulching is Pacific Aster & California Fescue.
The cardboard itself will not be visible, as it will be covered with mulch, and then it will disintegrate after a few months.
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| Cut the cardboard halfway through to the center and make a hole, so you can move the cardboard around the trunk of the plant or grass. In this case the cardboard was pre-sliced 3 times (from a case of bottles) which was still fine to use. |
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| On the left is a finished product, on the right is cardboard mulching in progress, and in the center, you can't see it until the next picture, is and example of the before, our native plant, California Fescue is being suffocated of sunlight from the invasive Oxalis weeds. |
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| OK, there it is, the California Fescue which was not even visible in the previous picture is now dominant with the cardboard in place. Once the card board is in place, cover it with wood chips, or other mulch, as was done to the California Fescue to the right and left. Note how these plants are surrounded by weeds such as Oxalis. Before the cardboard was put in place, it was almost impossible to see the California Fescue. With the protection against weeds given by the cardboard mulching, these California Fescue should succeed and thrive. |
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| An example of cardboard mulching being set up around Pacific Astor |
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| Its an easy one person job, but its always nice to have a friend help you. In my case my cat Chewy joined me. |
