I have used cardboard under wood chips as well as newspaper and find the newspaper will last longer than the cardboard. The glue used to hold cardboard together is not a problem in the soil.

I've used it, and it works wonderful. Just cover up any cracks in the cardboard with paper bags or several layers of newspaper, or the weeds will pop up in those cracks. (I didn't strip the grass/weeds, just laid the cardboard over them.)

I've used it too and I find the cardboard lasts longer than newspaper, and it's easier to work with provided you have a good source. I used multiple layers of cardboard to overlap the gaps. You will want to wet it down before covering with mulch. Worms love the stuff. But, so did the voles.

I just did this yesterday... I guess i'll find out soon. I used pretty thick cardboard, then compost and then woodchips. I plan on dropping some shrubs in @ some point...maybe next spring.

I have used cardboard and newspaper both with good weed suppression many times around trees, shrubs and even flowers. I am attempting a large scale restoration on a limited time and money budget and the newspaper mulch helps by requiring less replenishing to suppress the weeds (saves a lot of time and maybe some money). Sometimes I top off with woodchips or other mulch and sometimes I don't. The corrugated cardboard usually breaks down and rips quicker than newspaper or flat cardboard. Newspaper is the best of these for molding to the contours of the land. Pull out weeds or chop them to ground level before applying the cardboard or newspaper. Thoroughly wet the paper after you put it in place. It also helps to put a few sticks or stones around the edges to keep the newspaper in place. Then add wood chips or whatever. Also, if you want to plant through this mulch it breaks apart very easily when your shovel hits it unlike the synthetic landscape fabrics.

I've read in more than one post on this forum that newspaper lasts longer than cardboard. But I would expect that it would depend on the weight of the cardboard and the number of layers of newspaper that you're comparing.

Anyone want to be more specific? How many layers of ordinary newspaper would beat out...let's say: one layer of single wall, 200 lb/sq.in. corrugated cardboard?

The lady that wrote the lasagna gardening book, Patrica I believe is her name, says several layers of the newspaper. I did 5 layers of it and lapped over all the edges like 6". I've just done it so I can't tell you right now if it's better or not but most say it is. They say the reason the cardboard breaks down faster is because it's corigated and has oxygen in it.

Last year I mulched with aged wood chips under a Sugar maple, under two concrete bird baths, and in a couple garden paths, to help keep the weeds under control.

I used newspapers under the tree and pizza boxes in the other places. Then laid down 1-2 inches of wood chips aged about 3 years. (I got them for free from the town tree trimming).

Many more weeds grew back under the tree through the newspapers than the cardboard.

Here is what the mulch looks like under one of the bird baths where I used the pizza boxes - these were laid down kind of overlapping about a year ago and as you can see there aren't even any weeds growing through yet.

{{gwi:287241}}

Well, treelover knows way more about the weight and description of cardboard than I ever thought about! And gardnpondr has a good point about the air in the cardboard helping it break down faster. On the whole, I think the key is how thick the layers of whatever you put down are.

My main question though was about the glue in the cardboard. Should we be concerned about it?

Becky

Lol! No...all I know about cardboard is what was printed on the bottom of a box made out of what I consider "typical" corrugated cardboard.

I've been using up old moving boxes that my packrat dh wouldn't let me throw out 6 years ago. Now that they're almost gone, I'm probably going to have to start using layers of newspaper. I'm just wondering how many pieces of paper (approx) would have the same durability as the average cardboard box.

lol treelover, OR get your packrat DH to packrat you some more cardboard in. ;) I KNEW how I spelled corrugated wasn't right and when I saw your spelling of it, I thought, now that's right! LOL

You can get free boxes from most supermarkets, liquor stores, etc. Try appliance vendors for huge boxes.

I use newspapers, 8-10 pages to a layer, and overlap very well. Then add topsoil, coffee, grass clippings, chopped leaves in the fall, and other amendments to get it going.

We get a daily newspaper so they do accumulate quickly (NO ads or glossy paper, just newsprint)

Pizza boxes, Cereal Boxes, those kinds of things are made of paperboard, a denser form of cardboard. Paperboard would be something like 20 newspaper pages, while most all cardboard would be more like 6 to 8 pages of newspaper.
Because of the differing density of products this discussion is comparing apples and organges, not apples and apples.

I generally start all my lasagna beds with a layer of cardboard because it really suppresses the weeds well the first year. By the second year it's pretty much gone, though. I once laid maybe ten layers of newspaper over a hosta bed and covered with mulch for the winter, thinking that by spring the newspaper would have broken down. It didn't. Come March, the hosta couldn't get through the newspaper and I ended up removing all the newspaper, most of which was not only intact but still readable. If you want to suppress weeds long term, I'd probably choose newspaper.

Val