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elisa72_gw

How long to compost cardboard?

elisa72
13 years ago

If I put cardboard over my garden plot and keep it wet, how long will it take to compost enough to run over it with a rototiller? I've never used cardboard in the garden before and am having a terrible time with weeds in the veggie plot so want to try this method.

Thanks!

Comments (16)

  • robertz6
    13 years ago

    It won't 'compost' enough to break down, rather it will slowly separate enough after a period of wetness. How long will it take small pieces of cardboard to break down to the compost level when mixed in soil -- a few years I expect.

  • joepyeweed
    13 years ago

    The more you till, the more weeds you will get.

    If you put the cardboard down and bury it under mulch, my estimate would be one to two years depending upon how much life you have in the soil.

  • elisa72
    Original Author
    13 years ago

    "The more you till, the more weeds you will get." How so?

    "It won't 'compost' enough to break down, rather it will slowly separate enough after a period of wetness." Indeed, "compost" was not the right word. So how long to soften enough to till? I was hoping that someone had actually done this before and could tell me from experience, although I'll take guesses too!

    Thanks!

  • elisa72
    Original Author
    13 years ago

    I'm putting down the cardboard to kill the grass and weeds. I can't till now because it's too wet, and I want to build tall rows for planting. IOW, I'll be reshaping the plot from flat to trenches and rows.

    Perhaps I should just plan to pull off the cardboard as planting time approaches, reshape, then lay the cardboard down again and cover with mulch. Or something like that.

  • jonas302
    13 years ago

    You can till most spots after the cardboard has been down for a summer won't even know its there the wetter it is faster it will break down
    the no till crowd has a good point but in the end its your garden to do as you please in it

  • Kimmsr
    13 years ago

    Tilling soil brings up to the surface more long dormant seeds of plants that could be "weeds" which is why tilling after laying down cardboard is not necessary. Just how long it takes cardboard to be digested depends on how active a Soil Food Web you have.
    I have numerous time made new beds by laying newspaper down over the grass, and any "weeds", that were growing there and in a few weeks was able to plant that area without tilling. Cardboard and newspaper deprive and plants they cover of access to sunlight, which they need to grow, so they die. If any seeds are there and do germinate they also die because there is none of the light they need to grow.
    Put the cardboard down, cover it with some mulch to hide it and hold it in place, and in a few weeks you can plant there without the hard work of tilling, and you may find the soil is very workable not hard and compacted.

  • annpat
    13 years ago

    Putting down cardboard and then tilling it in would be pretty similar to not putting cardboard down and tilling.

  • ceth_k
    13 years ago

    Nothing is better said, annpat. I'm totally with him/her, elisa.

  • elisa72
    Original Author
    13 years ago

    Ah, NOW I get it! Thanks very much, everyone!

    Correct me if I've misunderstood, but since I need to make rows and trenches and want to use some of the native soil to make the rows, I'll remove the cardboard, skip the tilling and just make my rows.

    Then I'll re-use the cardboard in the trenches, where it will stay permanently.

    Sound good?

  • joepyeweed
    13 years ago

    May I ask what are you growing that needs rows and trenches?

  • kqcrna
    13 years ago

    pjames, it's nice to see you here again. I haven't seen you on this forum in a long time. I was sorry that HGTV didn't renew your show. Any plans for future shows, books???

    elisa, ditto what others have said. Put down cardboard and leave it in place to smother weeds. Just mulch over top of it.

    Karen

  • annpat
    13 years ago

    Here's how I do it in a vegetable garden. I plant non-row plants---like tomatoes, peppers---and mulch around them immediately. I far prefer newspaper to cardboard. Newspaper sucks itself to the ground, cardboard slips around. Where I'm going to plant carrots or beets or spinach, row stuff, I either plant first and then snuggle my newspaper and upper mulches up to the row after the seedlings are up or I, sometimes, lay the newspaper down and leave a gap for seeding. The second method is harder.

    If you insist on rototilling, you would till prior to laying down your mulches. A lot of us (including me) are opposed to tilling, although I still have mixed feelings about it.

    Cardboard and newspaper degrade differently in different climates, but your goal with mulches is to keep them intact. Not you, but other people seem to think that the cardboard needs to degrade. On the contrary, the longer it stays intact, the more effective it is.

    Other people may do it differently. You're going to love a paper mulch, whatever you use, I can tell you that. Your weeding days will be over.

  • tifbee
    13 years ago

    If you do use cardboard, remember to remove the tape, staples, and shipping labels...they will be there fooorrreeevvver.

    I agree with annpat on using newspaper instead of cardboard in the garden especially this close to planting time. The worms in your soil food web can break through the newspaper to get to the compost goodies on top better than with cardboard. Definitely use cardboard in your walkways as a weed barrier.

    Since cardboard does stick around longer than newspaper, I still use it outside the garden to lay down mulch, when I'm dealing with just choking out grass and weeds. Also, use cardboard in your walkways as a weed barrier.

    Good luck!

  • MsShelley
    13 years ago

    I'm a little bit confused. I certainly agree with newspaper and cardboard as excellent material to kill weeds etc What I am confused about is-- "growing right in the mulch." I have always thought that incorporating mulch with the natural soil would create a more balanced mix. Depending on what mulch you use, it can be very strong for new plants.

  • annpat
    13 years ago

    Mulch is never incorporated into the soil. Mulch, by definition, is always on top. As soon as you turn something into the soil, it becomes an smendment, not a mulch.