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How To Use Cardboard To Stop Weeds In Flowerbeds

If you are looking for an effective and inexpensive alternative to help stop weeds in your flowerbeds – using cardboard just might be the answer!

There is nothing more defeating than watching weeds take over your flowerbeds. What starts as just a few little sprouts here and there can seemingly turn into a jungle of greenery that can all but hide your plants and flowers.

Not only are weeds unsightly, they also steal valuable nutrients from your flowers. Even worse, they are time consuming and labor-intensive to remove. And once they establish, it seems like they just keep coming back stronger every time you try to remove them.

how to use cardboard to stop weeds in flowerbeds
Cardboard can not only stop weeds in your flowerbeds, but help your soil and plants both become more healthy over time too.
Getting Rid Of Weeds – How To Use Cardboard To Stop Weeds In Flowerbeds

Mulching your flowerbeds is certainly the first line of defense against weeds. Mulch not only keeps the soil covered to prevent weed seeds from finding a home, but also helps to keep moisture in and the soil temperature regulated.

But in many cases, mulch alone simply isn’t enough to keep stubborn weeds from pushing through. Especially in flowerbed spaces that have been overrun with weeds in the past. And in flowerbeds with those issues, even a thick layer of mulch will not keep existing weeds from shooting through.

There are certainly quite a few alternatives to take control of weedy flowerbeds, but many have their drawbacks. As already noted, removing them manually time and time again can be back-breaking work.

Although spraying can work in some cases, it can be expensive to use. Even worse, herbicide sprays can contain harmful chemicals – which can not only affect the health of nearby plants, but of you as well!

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The Pitfalls Of Landscape Fabric? How To Use Cardboard To Stop Weeds

For many years, landscape fabric has been the go-to choice for those looking to cut down on long-term weeding chores in their flowerbeds. But unfortunately, in most cases, it simply isn’t a good choice. Not for stopping weeds, for your plant’s health, or for your bank account either!

The drawbacks of using landscape fabric are extensive. For starters, it can be pricey. Especially if you purchase some of the thicker fabrics that are needed to stop stubborn weeds from poking through the soil surface.

But it’s not only the cost that makes landscape fabric a questionable choice. It can also quite easily affect the health of your plants. Over time, weed block fabrics do a poor job of allowing water and nutrients to pass through.

Even the best of fabrics will begin to clog as the mulch on top breaks down. When this happens, the plants receive less air and water into the soil. That in turn affects the root growth, leading to poor health that can even eventually prove fatal for some plants.

And with that loss of air and moisture underneath the soil, important vital insects and organisms can perish too. Most notably of which are earthworms – which happen to be one of the most beneficial of all organisms to work underneath the soil surface.

earthworms - using cardboard to stop weeds in flowerbeds
Landscape fabric and plastic can actually harm the earthworm population under the soil. Cardboard, however, actually can help them flourish!
And The Weeds Still Grow…

Making matters worse, when using fabric, its effectiveness as a weed block dwindles in just a year or two. Why? Because the mulch on top breaks down into a near soil like substance. Since it can’t break down into the soil below, it stays on top – letting new weed seeds germinate and grow.

Finally, once the fabric begins to break down and weeds form through it, it can make weeding incredibly difficult. And if you have to remove it to try to replace it – it can be nothing short of a nightmare!

Why Cardboard Is The Answer – How To Use Cardboard To Stop Weeds

The good news is that this is exactly where cardboard can come to the rescue in your flowerbeds. Unlike weed fabric, cardboard allows air and water to easily pass through at all times. Even better, it breaks down over time to actually help add to the soil’s value – not take away from it!

Cardboard also happens to attract earthworms and other beneficial worms. By placing it underneath the mulch in your flowerbeds to control unwanted weed growth, you actually increase soil life and activity and your flowerbeds nutrient value.

Adding to its list of benefits, in most cases, cardboard can be sourced quite easily for free with little effort. Whether it is using your own supply from deliveries, or sourcing leftover cardboard from local stores, it is readily and freely available.

And the best part of all with using cardboard under the mulch in your flowerbeds? It works like a charm to stop weeds!

Finding a supply of free cardboard to use as layer of mulch in your flowerbeds can be quite easy these days.

By simply installing a layer of cardboard on the soil and covering with mulch, you can prevent weeds from poking through for up to 6 months. An unlike rolling out and cutting around plants with fabric, you can place cardboard pieces easily and quickly wherever you need the protection.

Using Cardboard Safely – How To Use Cardboard To Stop Weeds In Flowerbeds

Surprisingly, most cardboard types are safe to use in flowerbeds. Some of the best and most effective types you can use are corrugated, paperboard and mat board. The key is to only use cardboard that does not contain wax coatings or heavy amounts of ink.

There are some cardboard types that you should always avoid. These include:

  • Avoid triple-walled or thicker cardboard. It decomposes but takes too long and is difficult for nutrients and water to pass through to the roots.
  • Avoid any cardboard pieces that have an excessive coating of wax or that are heavily inked. Wax coatings can make it difficult for nutrients and water to pass through. In addition, they also do not break down well and can cause issues for the soil and plants. Inks can have dangerous ingredients and without knowing the source, it’s best to not use colored cardboard.
  • Always avoid using cardboard containers that were designed to hold liquid. This includes milk cartons, juice cartons, etc. All of these types of cardboard will have heavy coatings to hold the liquid in, which is not good when it comes to helping plants get the water and nutrients they need.

How To Install Cardboard As A Weedblock – How To Use Cardboard To Stop Weeds In Flowerbeds

For cardboard to effectively stop weeds and break down efficiently, you always want to place it in direct contact with the soil. If there is any mulch or fabric existing, it first needs to be removed before laying down your cardboard pieces.

Overlap individual pieces of cardboard to seal off weeds from below.

Always use flat cardboard sections, as they will make laying mulch on top easier and much more attractive and uniform. To avoid any gaps where weeds can grow through, overlap each piece by four to six inches.

Always leave at least three to four inches bare around the base of any existing plants in your flowerbed. This allows plenty of air and moisture to the plant while the cardboard begins to break down.

The next step, watering, is critical to keeping your cardboard in place and increase its effectiveness. Watering the cardboard in helps to add weight to the layer and keep it from shifting. If you lay down dry cardboard and do not water it and then mulch over it, it can very easily shift or even blow up and out with strong winds.

Water the cardboard until it is fully saturated. Next, layer on a thick coating of mulch. Mulching on top of the cardboard is a must. First and foremost, it holds the cardboard in place. In addition, it also is much more attractive than cardboard laying in your flowerbeds.

Most of all, adding mulch helps to make the entire bed nearly weed proof with two layers of weed fighting protection!

How Long Will Cardboard Mulch Stay Effective – How To Use Cardboard To Stop Weeds In Flowerbeds

Depending on the type of cardboard you use, it can take 3 to 6 months for the cardboard to fully decompose. That is usually enough time to provide weed protection for an entire growing season.

Many gardeners will put a second application on in the fall under their mulch to provide all year protection. In most cases, however, a spring application of cardboard mulch is effective at keeping beds in great shape.

Here is to using cardboard in your flowerbeds this year to stop weeds! For more on eliminating weeds in flowerbeds, be sure to check out our article : The 3 Biggest Flowerbed Mulching Mistakes – And How To Avoid Them To Eliminate Weeds For Good!

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