6. Waste Paper and Cardboard. Put those old newspapers and Amazon delivery boxes to good use and fill the bottom of your large planter with a mix of them crushed down. Again, these materials will break down over time, so they're best suited for those repotting regularly.
If your budget doesn't allow for weed barrier cloth, you can add several layers of cardboard to the bottom of your raised bed before filling it with soil. The cardboard will decompose in about 4 to 6 months. Make sure to not use cardboard with glossy print and remove all tape first.
Cardboard boxes are well-suited for container gardening. Simply apply tape to the seams of your leftover boxes, poke a few drainage holes, add a plastic lining and growing medium and introduce your plants to their new home.
It's a great mulch, and prevents weeds from sprouting. Decomposing cardboard adds organic matter to the soil, improving your garden's drainage and boosting nutrient levels.
This no-dig garden hack is beautifully illustrated in a TikTok video from Brandon Gentry (@brandontgentry), below. Basically, you use sheets of cardboard in your planting area to kill off any existing grass and prevent those pesky weeds from popping up.
Cardboard takes approximately 2 months to decompose. However, instead of sending your boxes to the landfill consider adding them to your recycling or your compost pile. Cardboard breaks down fairly quickly when exposed to the elements, but stacks of cardboard can take years to decompose.
Cardboard and Paper Concerns
The glue used in cardboard boxes can contain chemicals, but the glue used to form the cardboard itself is derived from starches found in plants like rice, wheat, potatoes, and other tubers. This is perfectly safe to use in your garden and will eventually decompose.
Yes, roots can grow through cardboard, but only in certain conditions. 'Firstly, the cardboard must be moist enough to allow the roots to penetrate it. Second, the cardboard should be placed in a place where there is no light or air circulation,' Melody says.
Without sufficient moisture, cardboard and newspaper can create durable barriers that attract a couple of serious pests. It ends up that termites and voles love cardboard. By putting a layer of cardboard under your raised beds, you are putting out the vole and termite welcome mat.
Depending on the size of your plant and its pots, add a good layer of draining rocks to the bottom of the pot without drainage holes. Add enough rocks so that your plant's original pot can stick out of the decorative pot.
How to Use Pots with No Drainage Holes. Some experts suggest using a layer of pebbles as a sort of drainage layer in those pots without drainage holes.
Along with reducing weed growth in the garden, cardboard has many other advantages, such as adding organic matter to the soil when it decomposes, improving the garden's drainage, and boosting nutrient levels.
Since cardboard is biodegradable, you can add it to a compost pile. It'll break down pretty fast and serve as a healthy form of fertilizer for your soil and plants. The best part is that cardboard is entirely odorless, unlike some other items in a compost pile.
Cellulose Materials
In fact, termites will typically only eat the wood inside of a structure for the cellulose material it contains. This, unfortunately, means that any plant-based materials that contain cellulose, such as cardboard boxes, paper or even leaves, could attract termites.
Depending on how and where the cardboard is made, it can contain a long list of chemicals and glue compounds, both of which can leach into the soil. Add to that, many cardboard products also contain man-made ink compounds that can also soak into the soil as well.
Gardeners have different opinions on using cardboard in the vegetable garden, but certified organic growers can use what I call 'clean' cardboard – plain, unwaxed boxes with all tape and sticky labels removed, with minimal printing on the outside.
Cardboard is often made with pulp from pine trees, which can create a toxic gas called sulfur dioxide. When cardboard is dumped in a landfill and left to degrade, it releases this gas into the air, which can cause pollution when it reaches the air…or the soil below the landfill.
However, exposure to water or humidity is highly destructive toward cardboard mechanical properties. Water-soaked corrugated cardboard can easily collapse with irreversible shape distortions. Various treatments have been developed to render cardboard hydrophobic including wax layers and nanoparticle treatments.
Reusing cardboard for the garden provides compostable material, kills pesky weeds and develops a bumper crop of earthworms. Cardboard in the garden will also kill lawn grass and help you get a new bed ready for veggies, ornamentals or whatever you want to grow.
It can be placed at the bottom of a new raised bed to cover grass or weeds and stop them growing through to the top soil. Cardboard can also be placed on the dirt paths between vegetable rows in a traditional row garden, then covered over with bark chips to make an excellent natural pathway.
Steps for Preparing a Garden Bed with Cardboard
Cover the entire garden area with cardboard overlapping the edges so that weeds and grass cannot grow up in between the cardboard. If you are not putting soil on right away, weigh down the cardboard with something heavy like boards or rocks to keep it in place.