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adayfromnow

Help PLEASE! I started lasagna, do I need to start over?

adayfromnow
16 years ago

*sigh* I don't know how I got the impression I was doing this right, but I did. Too much research, not enough memory, I guess. Anyway...

Can you PLEASE tell me if I need to stop & start over or do something completely different!?

The area I'm working is about 10' x 12' & FULL of weeds. The soil is partially clay & partially loamy(?) [It's had a few years of organics land on it so it's better than it was before].

I did NOT till the ground first or flip over patches (I JUST now read that part). I just laid out a bunch of cardboard (1 layer thick) and spread about 1.5" worth of rotting leaves on top. I was going to get some humus & soil from the surrounding area & pile it on top of the leaves.

1) Will this "method" kill the weeds underneath?

I DO want to use this area for some plants that I have now because it actually gets decent sun. Most of the plants are in containers now. I wanted to put them in the ground but can wait if I have to.

2) Can I plant "into" my mini-sagna (I guess I would have to cut holes in the cardboard because it's too shallow)? OR

3) Would I be better off doing a raised bed here?

I'm so frustrated. No matter how much research I do, it seems every time I turn around I realize that I've done something WRONG. Maybe I should just give up on trying to garden & find another hobby!

Sorry. Thanks for the advice & thanks for listening to me WHINE!!

- Mari

Comments (6)

  • Judy_B_ON
    16 years ago

    Tilling is not needed with lasagna beds.

    You need a thick enough layer of cardboard/newspaper and soil/mulch to stop the light getting to the weeds, about 4 to 6 inches in total. One layer of cardboard may not be enough. I usually use 5 to 6 layers of newspaper and 3" to 4" of mulch, but I am planting native prairie plants, not veggies.

    It takes about 6 weeks to kill the weeds, do not dig a hole through the cardboard until you are sure the weeds are dead as the weeds will grow through the hole. Cardboard takes longer than newspaper to decompose, so you may need to wait until the end of summer to plant.

    If you think the layers aren't deep enough, cover the leaves with newspaper, then add soil on top of that. For a 10 x 12 area, 3 inches deep you will need about 30 cubic feet of soil or slightly more than a cubic yard. Can you get that much from the surrounding area -- that is 8 to 12
    wheelbarrows full? I think a layer of mulch on top of the soil will help prevent new weeds from sprouting.

    Make sure the cardboard and newspaper are moist or even wet when you put them down, it speeds up decomposition.

    Here is a link that might be useful: Lasagna Gardens

  • adayfromnow
    Original Author
    16 years ago

    Thanks SO MUCH, Judy. I'm really glad to see that it's not necessary to till or turn first. I may, however, slide my bed over while it's still lightweight & pull as many weeds as I can, as I have found that I enjoy taking my frustrations out on the weeds! Then again, I may not. lol

    Two things I have in abundance here are leaves & soil from the wooded areas. I'll just swipe those from areas where I don't intend to have a "garden". But I'll probably also get some cheap topsoil from HD to mix with my good stuff so I don't have to do quite so much shovelling.

    You're right that it is a huge area to make deep enough for planting. I think I'll slowly build up the lasagna & just build some smaller boxes on top for planting now (less soil & less work).

    I really appreciate your help. You have no idea how much!

    Thanks,
    Mari

  • Judy_B_ON
    16 years ago

    You don't need to pull the weeds.

    Be careful with purchased topsoil, it may be full of weed seeds. Compost, peat moss and mulch are better materials.

  • kahurin
    16 years ago

    weird ive never heard of lasagna planting LOL but i thought i would post about killing weeds i read in a book that if you take a pond liner that big black rubbery thing and lay it out on the weeds for a day or two on a hot day every thing would die it made sense :D but i think theh guy was talking about a hot day like more then 90 degrees out i live in alaska so i think i would have to leave it out there longer :S it only gets about 80 here

  • meldy_nva
    16 years ago

    Kahurin, that's a form of "solar sterilization" and while it can work very well in killing off the weeds and weedseeds, it's a wee bit tricky to do. The plastic is used to permit a buildup of the solar heat. The soil should be dampish and one must fasten all the sides of the plastic to the ground so that the steamy heat doesn't dissipate. I've read various estimates, but it takes in the vicinity of 10 days of consistent high heat to be effective. (The sunny day temps will get to about 140°F)

    OTOH, just putting heavy black plastic over an area will kill most weeds in a week or two due to the lack of sunlight; it just doesn't kill the weedseeds that in the soil.

  • squirrellypete
    16 years ago

    Not to worry Mari. As others have said tilling is not necessarily needed. My tiller was never effective in this rocky, hard clay and usually just bounced all over creation so I stopped trying. I've been doing exactly what you did for the last two years with great results. I'm slowly reclaiming what I thought were impossible areas just by putting down a couple of layers of cardboard right overtop of thriving weeds and making sure it overlaps properly to prevent sunlight from penetrating. Then I cover that with a thick layer of mulch/dirt, etc... (heck, sometimes I don't even mulch if it's an area that isn't easily visible and won't be an eyesore. If there are already established plants in the area I just cardboard around them and pull whatever weeds may reach out around their bases. Otherwise I just wait until the weeds are dead before planting new things. Even if a few stray weeds or runners find a way through it's much easier to eliminate those few once all the rest are dead. I had an area that was completely taken over by wild blackberry vines taller than me. They spread 15 feet closer to the house in just one season! So I whacked everything to the ground and then blanketed with the cardboard in the summer and everything underneath is dead now(yay!) I have yet to find a chemical brush or weed killer that actually does what it's supposed to and kill the root of the annoying weed grasses, thorny vines, etc... This takes a little longer but will not waste your money or time like spraying.

    I also just borrowed a large rubber liner from a relative and I'm going to use that to try and retake my gravel driveway and parking area one section at a time. I have heard this "solarization" is not always recommended for areas where you intend to plant though because the heat will also kill the beneficial microbes & organisms that are in that soil. Weeds in gravel are an awful pain. I look forward to a day when we can afford to blacktop it.

    Sincerely, Danielle

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