Cardboard Weed Barrier

Weeds can take over after just a few days of not weeding. I’ve discussed the many ways of getting rid of weeds naturally like natural weed killers before, but today I wanted to show you how to use a cardboard weed barrier to suppress the weeds.

How to suppress weeds with cardboard

Using Cardboard as a Weed Barrier (Tips)

Although there are obvious pros for using cardboard as weed barriers, but there are also some cons that you should learn about before using cardboard weed barriers.

Don’t use Colored Cardboard

Most colored cardboard will have toxic dyes that you don’t want in your soil; it’s better to use the most plain cardboard you can find. We’ve often used ones with writing on them simply because it’s hard to find plain ones, but steer clear of the fully colored ones.

Take the Tape off of the Cardboard Barrier

Can I be honest though here? I leave it on until it’s been raining enough times and then rip it off… I’ve found it’s easier to come off that way. You do end up with bits of tape underneath, but I’ve found it easy to remove later in the season. Much easier than taking it off from dry cardboard. But really, yes you want to remove all the tape first, it’s something else you don’t want in your soil.

Place Rocks or Mulch on Your Cardboard Barrier

One gusty wind and your cardboard will blow away, especially if you’re using smaller pieces. We overlap them and add heavy rocks on them before we add the mulch.

How Long Will a Cardboard Weed Barrier Last?

The cardboard will get slippery and mushy over time so it’s a short-term solution

Even though cardboard can hide the weeds instantly and block out the light to your weeds, it will decompose within a couple of months (you’ll see an accumulation of worms underneath as they love it!). Cardboard is great to use if you’re building a lasagna garden bed (you can see the process of one of ours below) but you’ll still need some mulch over top of it eventually. Be wary after many rainfalls it can be a little slippery too!

Building a permaculture lasagna garden bed

Should You Use a Cardboard Weed Barrier?

Cardboard can be a great quick fix for weed control in your garden and is perfect for lasagna gardening or putting at the base of new raised beds. It won’t give you permanent weed control however so you’ll need to come up with something for the long-term like adding mulch on top of the cardboard.

How to suppress weeds in your garden with cardboard

8 thoughts on “Cardboard Weed Barrier”

  1. Your posts are so helpful and your ideas are usually something that most of us can afford….like this cardboard/lasagna. I really enjoy this blog 🙂 Thank you.

  2. I use cardboard all the time. I stalk all the recycling bins around the businesses in town to collect enough for my garden! My husband thinks I’m cardboard-crazy but he has no idea how crazy I’d be if I didn’t have it for paths, weeds, etc., in the garden.

  3. I also use cardboard in the garden. Mainly on areas between beds where I want to keep down running grasses and have somewhere fairly dry to walk on. I put mulch on top and then when it is all rotted down I can pull out weeds more easily and plant things there that I want. I also use the cardboard in the compost, just tear it up a bit and it rots down. Wish I’d had your tips before, as I’ve found that sticky tape is very annoying later. Also cardboard that is covered with moisture proofing needs to have the plastiscised paper ripped off and that’s a job!!

  4. I’ve used cardboard with grass clippings on top every year in my garden, and every year the diseases on my plants gets worse. when I peeled back the cardboard, there was always white mold spores between it and the clippings and under the cardboard on the soil. I ripped it all out early in the season this year and have to use a copper fungicide spray every week now to keep it at bay. I will not be using cardboard again! Next year I will use a mulch of straw or wood chips. That’s all.

  5. I like that you mentioned that it only takes one gusty wind to take your mulch away. My wife and I plan to start a garden and this helps a lot. We will need an expert in weed control services to help us out.


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