Using Cardboard for New Garden Bed
An Answer to a Gardening Question from a Reader
Hi Rachel, How are you and the garden these days? A question. I wondered if I used cardboard right over my lawn to make a new planting bed then added compost and dirt over that would it compost the lawn turf below or should I remove it or till it first? -H
The answer to this question lies in the timing in which you wish to transform the lawn into usable garden. Also the amount of effort that you wish to put into it is important.
In my post on breaking new ground, some of this method is mentioned. The description of laying down cardboard and covering it with straw is the first step. The straw at first has the job of holding down the cardboard. One must put enough on top to keep the winds from dislodging it. When I don't get enough on, I have to run around the field gathering up the cardboard, or sometimes paper. When we run out of cardboard we use sheets of newspaper. I've heart that the paper is enough to keep the weeds from growing up through. Of course, again the straw is useful as a weight.
Later on, as the cardboard breaks down, (and this takes quite a while), the straw becomes home to the worms and other beneficial soil critters who help break down the straw into humus, that is, soil.
March 19, 2009 The edge of the potato field as its built.
The boards are holding down the newspaper, waiting for the next layer of straw. It was a very windy day.
I have a new field laid out with paper and straw that I am going to be using this year, but not for the soil beneath it. I'm going to plant potatoes IN the straw. Their roots will likely go down through the straw and somewhat into the soil as they age. But right now, the job of that paper is to keep the weeds and grasses from growing. Hopefully as that green material spoils and rots, the bugs that make a living out of eating live roots will get all they can out of that plot and will move on somewhere else. Some sources say to leave a field for 2 years so that the lawn bugs will leave before you can use it without problem for a garden.
In the garden where we started with tilling, I spent all Summer dealing with the bugs that normally live in a pasture. Afterward I researched a bit and I found that those who know (can't remember the reference now, sorry) say that a plot of pasture or lawn needs to be repeatedly tilled, once or twice a week for several weeks until the plot would be ready to plant. Of course I didn't do that. On one day the site was gone over three times with the neighbor's tractor's tilling attachment.
March 17, 2008 The Plowing o' The Green
Tilling seems to be helpful to start a garden. However, all the plant matter that is cut up and remains on the surface has to be removed so it doesn't grow up again. Also many worms are killed and the soil becomes very disturbed. Keeping healthy soil is a science in itself and studying this usually leads to the development of a "no till" garden. This is what I am using now. Keeping a good mulch of straw over everything holds down the weeds, keeps in the moisture, gives good eating to the worms who increase the health of the soil in innumerable ways.
Another question is regarding the type of grass that will be covered up. Grass which is tame and only spreads by seed is much easier to deal with than grass which spreads by the roots (or are they called rhizomes?). If you have what is called Bermuda Grass, or Crab Grass it is much more difficult to get rid of. If you put cardboard down over it, the shoots seeking out will go to where the cardboard is not and will continue to spread. I've been told that the only way to get rid of that is to put black plastic over it, to remove the light and burn it with the heat that is trapped in the black.
Now your idea, Heather, is very interesting, to suppress the lawn and then cover it with soil for planting. Hmmm. I guess you'd want to put a frame around the edges to keep the soil in. You'd also want the cardboard to be thick enough for the roots not to break through it right away until the weeds died. That is, use cardboard from boxes rather than from shirts. (Do they still fold shirts around flimsy cardboard?).
There's a book on my shelf which I have not yet read, called Lasagna Gardening, which I believe has a recipe similar to what you are suggesting. Layers of paper, cardboard, compost form a bed in which to plant, feed and grow one's vegies.
All in all, I'd say that you have a good idea brewing. How about taking pictures and letting us know how it goes?
And the other question you asked "How is my garden going?" Tonight will be a freeze, with possible snow, so the plants that are eager to be planted have decided to shy away from the winter experience and are still taking up room in the greenhouse. The tomatoes would like bigger pots, however in their little cells they can all be under the lights, high up in the warmth. There doesn't seem to be enough room yet to repot them (a job that is high on the list), as the Bok Choy, Kale, Chinese Cabbage and Lettuce, refuse to leave the nice warm and protected greenhouse. As soon as I plant them outside I'll have to construct insect proof fabric tents for them too.
Look at this bug that I found IN the greenhouse!
On the other hand, it IS Spring, and there is joy and beauty here.
Much Joy to You, Dear Readers!
