Controlling Weeds With Cardboard

A colleague was telling me the other day about the uncontrollable weeds in his backyard which are ruining his enjoyment of his large outdoor space. He said he has been resorting to Round-Up, a chemical weed killer, and that he and his wife were so frustrated by the "Weeds Gone Wild" problem that they were planning to pave the entire backyard. Sacrilege!

He was very surprised when I told him it is possible to control weeds without chemicals, by mulching.

Mulch is any type of material that is spread or laid over the surface of the soil as a covering. It is used to retain moisture in the soil, suppress weeds and keep the soil cool. Organic mulches include bark, shredded or chipped, compost, manure, grass clippings, newspaper, cardboard, shredded leaves and straw.

I've been using cardboard as mulch for a while now and it's been working out great for me.  After speaking with my colleague I remembered I still had some seedlings that I needed to get into the ground, so I turned the soil, laid some cardboard, cut holes for the seedlings and did some planting.  Here are some photos of what it looks like right now.

The cardboard has many advantages. It's cheap, easily available and gives a complete coverage. (In my photos you can see I still need to cover up the corners that are exposed). You can cover it with a more attractive mulch like wood shavings or straw and the water will seep right through the cardboard to the plants, but since no light hits the weeds they die. I have picked up cardboard after having it down for a couple of months and it is pretty cool to see how total the destruction of the weeds is.

If you try cardboard as mulch use only plain cardboard, not the smooth, colored type that a vacuum cleaner or toaster oven might come in. You don't want the ink leaching into the soil.

Tomorrow I will talk about planting on the parkway. Here's a photo of the parkway in front of my house, which you can see is challenging because it is heavily shaded.