The Lasagna Method: Get Rid of Weeds and Sod the Easy Way
If I could somehow go back in time and give my new-gardener self just one piece of advice, it would be this: Use the lasagna method when starting a new garden bed. Of all the tough gardening chores, removing old weed-infested sod (or any sod, really) rates right up at the top of the This-Really-Bites list. Oh, how I wish I had known that I could just smother stuff rather than wrestle it out of the ground—the sheer force propelling me off to the chiropractor to fix my aching back once again.
There is no such thing as maintenance-free gardening. But gardening doesn’t have to be on a mission to kill you either. This is the beauty of the lasagna method. The goal is to keep light and, to some extent, air and water, from reaching the weeds and turf. There are no exact rules for this process, so I’ll explain what I do and you can modify the strategy as you see fit.
Run your mower over the area you’re thinking you’d like to turn into gardens so that weeds and turf aren’t super tall. Use your garden hose or a length of rope to mark the outline of your new bed. Next, cover the sod, weeds, or whatever other horrors are lurking in that spot, with five to 10 sheets of newspaper. (Newsprint is fine because the dye is vegetable based, but don’t use those glossy ad pages.) Overlap the edges to close gaps as best you can. And keep a hose handy so you can wet the newspaper as you go or it will blow all over the place and drive you nuts. You can use cardboard rather than newspaper if you want to, but it takes longer to break down and, depending on where it’s from, it can contain some glues that you might not want in the soil where edibles are grown.
Once the paper is laid out and watered, cover it with about 4 to 6 inches of topsoil mixed with the compost of your choice. (I really like mushroom compost at the moment.) Feel free to add in other organic matter too, such as leaf mulch, coffee grounds or rice hulls. Peat moss will also help to improve drainage when used as part of a soil mix in a large bed. But I’m trying to steer clear of it after learning that the process used to harvest peat moss often causes the demise of the wetlands or peat bogs in which it grows. It’s a personal choice, but I thought I should explain why I’ve omitted it here.
Cover the entire area with about 3 to 4 inches of organic mulch. I usually use wood chips, but any organic mulch will do. Just be sure to cover the soil well so you don’t get a big weed patch sprouting up out of it again. If you don’t feel like getting wood mulch or don’t like using it, you can cover the area with a tarp and use some rocks to hold it down. (See our lovely blue tarp pictured above.) In the heat of the summer, it takes about two to three months for turf and weeds to die back to where it’s easy to plant straight down through the layers of soil, newspaper and dead sod/weeds. You can plant sooner, but it will be more of a struggle to dig down through the layers.
One last thing: If you’re killing off weeds and turf with the lasagna method in the fall, you can add lots more organic matter that will take additional time to break down. Things like mulched leaves, coffee grounds and filters, fruit and vegetable scraps, sawdust, tea bags, shredded newspaper and grass clipping are all good choices that will add nutrients to the soil and improve its structure, too. As long as it’s well covered with mulch, it shouldn’t attract raccoons or other marauders over the winter.
*A version of this post appeared in the September 2012 issue of Northern Gardener.
Sarah Wooller
How I long for decent garden blogs – but this one has a good feel about it. I’m not sure I have the time to do this in quite the same way, but I guess I could always put pots on top whilst it looks such a mess. Any idea how long it takes to kill off bindweed?
Meleah
Thanks, Sarah! This does take time, but it’s so worth it. If you just can’t wait to plant, you can start digging down through the layers to put in plants after about one month. You’ll just have to dig through more newspaper, which isn’t that troublesome. The hotter the weather, the faster things will break down. As you probably know, bindweed is tough to kill off. Like other weeds, it will die if you cover it so that no light gets in. The hitch here is that unlike other weeds, such as creeping Charlie, it will keep germinating in the soil and returning like a zombie in a b-movie. It can take up to three to five years to kill the stuff completely. But you can definitely knock it back quite a bit by using the lasagna method over the whole area where it’s growing. Then, if you see it popping back up, try putting newspaper layers back over the areas where it’s growing. It’s kind of a mini lasagna in the midst of the garden. I do this in spots all the time to kill bindweed and other stubborn weeds and it works very well. Good luck to you!
rickngentilly
great advice.
i dont know if this would work as far north as yall but down here @ 30 x 90 long. by lat. clear visquine solar cooks the weed seeds and other stuff you dont want in your new bed pretty quickly.
that went against every thing i thought when i was using black visquine thinking it would absorb more heat.
hope this helps.
would like to ask you a question.
the u.v. is pretty intense down here six months out of the year.
that put’s a real butt whipping on plastic.
i’ve been studying and collecting parts and info for a rain barrel cistern system.
i’ve scored some old olive barrels made from plastic. i like them because the top screws off and you can put a peice of mesh on top and than screw the rim back on making the input large and keeping the mosquitos out. a big concern in the hot humid south.
so my question is can i put something like amor-all from the car store on the plastic? is there some other way to coat plastic to slow down u.v. ray breakdown ?
i used to use 5 gallon buckets from work to catch rainwater from my gutters. after two years they would fall apart and crack from the u.v.
it would be cool if you could take a totally unscientific poll on this subject.
thanks in advance.
p.s. yall’s front yard is what inspired us to put three new beds in our front yard next week , a.k.a. my last week of vacation before the turista hurricane hits our shores.
thank you for any feedback you can send me on the plastic rain barrel longevity project.
your pal , rick n gentilly.
Meleah
Hey Rick,
Good to hear from you! Are you guys using the plastic to cook the weeds for those three beds? If so, could you take some pictures and email ’em to me? I’d love to see what the process looks like and the before/after shots.
Good question about rain barrels. There isn’t a whole lot of research on the safety of rain barrel water, but many people, including me, advise against using it on edibles because of contaminants that could be in the water due to things like mold and fungus on roofs and gutters, pollutants and chemicals in the runoff from roofing materials and bird poo. But even if you don’t plan to use the water on things you’ll eat, it’s a good idea to use barrels made of food-grade plastic, which it sounds like you’re doing.
The only thing about reusing the olive barrels, as you know, is that they don’t contain the UV protection coating that commercial rain barrels do. To prevent bacterial growth, it’s best if the barrels are dark rather than light. Is that the case with yours? I did some quick research trying to find a UV protection product that you could apply yourself, and I can’t find one. So I’m going to put the question to some master gardeners I know and get back to you. Armor-All is an oil-based product, which I can’t imagine won’t leach into your soil in pretty short order. So I wouldn’t use that. I’ll get back to you.
cindy
I have a yard full of wisteria runners and evergreen vinca and their runners. Can Lasagna gardening wipe them out or will they just grow through the paper? I’m thinking of putting very thick layers of well overlapped papers down, then make a lasagna garden over it 2′ or more and just let it sit for a year, no digging, no nothing. Just let it hopefully, rot. Will that work?
Meleah
Hi Cindy,
I just found your note. It seems that it was filtered out as spam. Sorry about that. Lasagna gardening will work to smother the vinca, but not the wisteria. I know because I’ve actually tried it with both. I think wisteria just has to be ripped out, really. But you should be able to smother the vinca very easily in a couple of months in the summer when the weather is hot. I hope this helps. m
Sharon
Have you tried WeedBGon by Ortho? I’m still in the learning stage of trying to decide what to do about this creeping bellflower before it reaches my gorgeous hostas. Some of it is accessible but some of it is in my lilacs, phlox, and mums. So should I remove and discard those plants for better access or don’t disturb the soil? I don’t know how to handle the affected lilac shrub. ANY GOOD ADVICE IS WELCOME! Thank you.
Alicia
I’ve done this to kill weeds and we covered it with wood chips and then later added some plants – it’s been a good 6 years or so and it’s still weed free and looks great. But now I have a large area (my backyard) that is full of weeds and goat head stickers and very little grass. We live in a very arid drought stricken area ( New Mexico) and I just want a little grass in the middle to look at. I’ll put crushed rock around the edges. Do you think I could do this and then plant grass seed? I was thinking of doing it in sections because I have very curious dogs that I will need to keep away. And should I plant grass seeds immediately or wait?
Meleah
Hi Alicia,
I’m not that familiar with trying to plant grass seed in your area, particularly considering the drought that you’re experiencing. You could definitely use the lasagna method to get rid of unwanted things. But before you sow seed, I would talk with someone at a local garden center about timing to be sure you shouldn’t wait until the fall when it’s cooler. I hope this helps. – Meleah
Amy
Thank you for your post! I am very excited to sheet mulch two areas of my front yard that are mostly covered with sod. The sod was laid down 3 years ago with plastic mesh embedded in it. My question is whether I must struggle and remove this mesh before sheet mulching or if I can proceed with the fun part and hope it works lose more easily later.
Or, best of all, can I ignore it and not worry about the future???
Thank you!
Meleah
Hi Amy,
I’m not sure about the mesh, but if it is actually plastic and not some biodegradable materials, I would guess that you should remove it before trying to use the lasagna method.
Robin
Hi,
We have used this technique in our front and back yards. We have a clover like weed popping up in many spots. I tried laying more newspaper and cardboard on the first section I saw in the front yard and pulled out other weeds; however, the weeds continue to spread in new areas. Any thoughts other than having to do a new layer of mulch?
Thanks,
Melissa
Hi Meleah, I live in hot and humid Tampa Florida, and I was wondering would I still have to wait 2-3 months for the weeds to die- since summer is approaching? Also, can I plant new grass with this method? Thank you
David & Eden Vaning-Rosen
I am a totally frustrated newbie from Clearwater, FL looking for a paid helping hand to replace overgrown weeds in my long, long neglected sloped run-off pond-facing backyard. I need a step-by-step program that will predictably handle the overgrown weeds while not disturbing the vines that have taken years to spread over the lawn. I like the idea of using nature to counter nature and have all this coupled with very low maintenance, perhaps replacing the entire weedy viney lawn with a bed of clover, since it is nearly impossible to access by mower (Perhaps metalic weed whacker?) I know fair-to-middling about gardening. Is there any hope here? Oh, by the way, we have buried septic drain fields in all this that came with the house. Those drain fields have never been dug up nor reamed out. – David R.
Patty
I have one weedy area around the side of my yard with persistent weeds. I have managed to control them but want to plant sod. Will i be able to plant sod after using this method and how soon after laying organic matter? The rest of my yard is lovely with gardens and manicured grass. I am so ready to fix this area.
DJ
From Idaho here. I find this article cute. how absolutely adorably cute that a teeny layer of news paper and a couple inches of dirt is a weed barrier where you are! I have commercial grade plastic weed barrier with bark on top and the weeds grow through that. I have cardboard with grass clippings and shredded paper a total of six inches thick on top, and the weeds grow THROUGH that. I even have plywood with straw over it, and the weeds are growing through knots or cracks in the plywood! A layer of newspaper would be like “thanks for the sunshade” from the weeds!