Rolls of cardboard under mulch to kill grass

Get a big roll of kraft paper off amazon or staples

I don’t take all the tape off. I layer a few inches of mulch or woodchips each year and the garden is no-till. Haven’t seen any tape surface yet.

Do you have a source of information which confirms this statement? I have read countless articles and books with the opposite viewpoint, and have personally seen the benefits of adding a cardboard layer in my own planting beads. I had at least 4 earthworms in each of the tiny holes I dug for my gooseberries this year after installing my beds last year. The robins love hunting all over the beds, I watch them do so daily from the abundance of worms.

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I have never tried just putting down cardboard on top of my field grass then compost and mulch…

Seems to me you would have a layer of good stuff then immediately under that a layer of compacted soil in whatever shape it was prior.

I may be somewhat old fashioned with tilling… but it works great. I normally till up a 8 ft wide strip of field. Just 4-5 inches deep… this breaks up all of the grass and grass roots… and mixes it with the soil… composting it… I usually do that a couple times over a couple weeks… then I will add compost and till that in or layer it in… and I will then rake that 8 ft wide strip up into a 4 ft wide raised bed… then just cover it all with a deep layer of mulch.

I like to do this the summer before… then plant it in the spring.

When I rake that mulch back to plant in the spring the soil is in great shape… deep and lose and loaded with earth worms. I can normally plant even fruit trees using nothing but my hands.

You don’t have to use cardboard if you do that… grass does not come up thru my mulch.

I can see how that should work well if you were absolutely against tilling.

I have a hard time believing that a layer of cardboard or anything cardboard sized would actually kill earthworms. Any time you find just about anything large/flat laying on the ground (lumber, plywood, sheet metal, carpet, etc.) and turn it over… you can usually collect enough for a fishing trip.

TNHunter

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Sheet mulching with paper or cardboard works. I erase parts of lawn with just a thick mulching of hay/straw. Sheet of plywood? black plastic? Yep. Its all about blocking the light. Just mow it really short first. It will be gone in a month.

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Linda Chalker-Scott and her students have a few papers on gas and water exchange across different sheet mulch materials (link). The short of it seems to be that wood mulch alone ( particularly a large format arborist-type mulch) is sufficient to kill many lawn grasses by elimination of light, while still allowing gas and water exchange. Cardboard limits exchange and can become hydropobic if allowed to dry (e.g. exposed edges if mulch is dislodged). However, it breaks down relatively quickly and can subsequently be recolonized by soil life. Newspaper is much worse for gas exchange and takes longer to breakdown. My two cents is that cardboard is probably fine, but straight mulch is better if you can apply a sufficiently thick layer. However, card is probably fine the long run and if you go with cardboard, the less coated the better.

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I let the worms do this for me! :slightly_smiling_face: having the grass>cardboard >compost >mulch, I am at a minimum of 4-6" of soft, happy soil high in organic material mimicking the forest floor. I am sure this method does not work as well in all climates, but on the east coast it’s a great low labor way to go. Those worms do a good job of breaking up the hard “crust” as they munch on the grass above it.

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literally my whole property was planted like this. after losing 2 apples by trying to grow in ground i went to 12in high raised beds and mounds. put down a larger area than needed of double cardboard, mound soil on top or fill a raised bed . planted tree/ bush in them and mulched heavily w wood chips. i planted every thing in rows so i eventually filled in between the trees with cardboard and woodchips so i didnt need to mow around the trees. just go up a row and down the row. i then in the last 3 yrs., been planting mecinidals and fruiting groundcovers in between and around the trees and bushes. its filling in nicely with all types of plants and bee attracting flowers. once its grown in enough it should fill in so it will have a tunnel effect when walking the rows and shade should keep the grass from growing much or at all. :wink: you dig in those chips ive been adding in there for 7 years now, and its about 8in. thick of nice black soil with tons of worms. the mounds and raised beds settled some but are still growing great plants/trees. if i planted these directly in ground they most likely would have died in my rocky clay soil. cardboard and woodchips kept me growing when it looked hopeless other wise. and of course great ideas from you great folks here and on permies.com.

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Permies is a great site too, but the ads and navigation leave something to be desired. Your point about amending “less than ideal soil” is an important one Steve. Under my grass is a bit of topsoil on top of mostly coal mine spoil, so it’s important for me to amend that stuff with the best possible upper layers. I guess I’ll take coal spoil over bedrock or solid clay, at least it drains…

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@disc4tw — I have pretty good topsoil in the first 4 -5 inches… then some nasty sticky red rocky clay.

When you go a little too deep… start pulling up some tiller jamming boulders…

If I break up a 8 ft wide strip 4-5 inches deep… which includes all the grass and grass roots… and only do that as much as needed. (no need to overtill)… l am sort of making a organic matter rich smoothie for the worms :slight_smile:

Tilling a couple times over a couple weeks… does not make your soil devoid of worms…

When I finish that second tilling and add lots of compost and then rake that 8 ft wide strip up into a 4 ft wide raised bed… there are always lots of worms present…

Feasting on that organic matter rich smoothie…

After I get it all raked up… I have 8 to 10 inch deep organic matter rich soil… loaded with earth worms… that I cover in deep mulch.

When you plant in that the next spring…it is oh so good. Worms galore.

What ever you plant in that will thrive…

TNHunter

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id prefer to do that to my grass but right under that is loaded with fist sized rocks. i tried the tilling thing when i did my raspberry patch. the 1st 2 xs i tilled i took out half a pickup up load of rocks. so much so i had to buy soil to put back in there because of the depression left after the rocks were took out. told myself no more of that! :wink:

I do collect moving boxes, if they’ve been repeatedly used they have so much tape it’s silly. I take a lot off if it can be ripped away easily, but that is a winter activity. Mostly go to Aldi for boxes now, they don’t really have tape. Cardboard sheet from drink and water pallets, tops for boxes of paper plates, etc. Boxes from fruit are usually very thick.

For soil solarization (killing the stuff under the plastic), clear plastic is more effective.

I totally agree with you, but when you stack layer of cardboard, all bets are off.

If you have a heating and cooling business (or any appliance store) fairly close, you should stop in and ask them if you can take their cardboard. Or better yet, if they’ll save the large boxes for you. Our local heat/ac business puts in a lot of water heaters, air conditioners, and various furnace systems. Some of the boxes are huge and very thick, good cardboard. It all gets recycled, and they don’t mind if I take the large boxes out of their recycle bin. It is so much faster and easier to get the giant boxes than all the little ones.

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How many folks know that earthworms are invasive, introduced alien species that are detrimental to many North American forest ecological systems?

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I’d like to try sheet mulching but had an armillaria scare with some wood chips I got from an arborist last year. Then this year found some serious vole damage. Mulch gives them cover, so I think it rules this method out for me, which stinks because my soil is very sandy and can always use more organic matter.

block bait put in 12in. long 3in. pvc pipes with 1 end duct taped off., put around the edge of your property in late fall will elliminate that issue. has for 6 yrs for me now. i mulch my plants with a large load of arborist chips every spring.

That’s a bit misleading. not all earthworms are invasive. approx 1/3 of earthworm taxa are invasive non natives. since they outcompete natives, there are larger populations of invasives vs natives. jumping worms are the most recent invasives to establish themselves in my area. while invasives can cause damage to ecosystems by disrupting nutrient flow/mycorrhizae, once established there is nothing that can be done to remove them from the ecosystem that won’t disrupt native populations too. while everything should be done to prevent the spread of invasive species into new ecosystems, sheet mulching to attract all decomposers, native and non native, isn’t going to cause any more harm than those non native earthworms have already caused to that ecosystem.

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As mentioned we reuse old cardboard from packaging items are delivered in. After the growing season it is mostly broke down but any remaining becomes worm food in the compost pile. Ruth stout used old hay but no matter what you use tilling is not necessary unless their is severe compaction.
The old books are inspiring gardening material

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