Raised garden beds are perfect for growing vegetables or any other plants in gardens with bad soil. This is because they allow you to build a new garden with its soil and ecosystem in the air.
Raised garden beds are also perfect for minimizing pests. This is because they are usually lined with a material to prevent pests from coming in through the bottom. The fact that they are off the ground level also minimizes the number of pests that can get to them.
Because of their benefits, raised garden beds are increasingly becoming popular in both urban and rural areas across the world. More and more people are constructing them to grow their food or have fancy gardens in their backyards.
In this post, you will learn two important things about raised garden beds. First, you will learn why it is not a good idea to install a raised garden bed directly on grass. Second, you will learn about what to put on the bottom of a raised garden bed.
Why it is not a good idea to install a raised garden bed directly on grass
If you install or construct a raised garden bed directly on grass and do not line it with anything, the grass and any weeds in it will grow into your raised garden bed and affect the plants you have on it. Therefore, to avoid this, it is advisable not to install a raised garden bed directly on grass or to take care of the grass and the weeds below your garden bed before filling it with soil.
You can take care of the grass and the weeds below your garden bed in two ways. First, you can kill both via soil solarisation. Second, you can block them from getting into your raised garden bed by lining your raised garden bed with a good garden bed liner.
Soil solarisation is a procedure that is normally used to kill both grass and weed on patches of land. It involves covering a specific area with a plastic sheet for six weeks. The sheet is supposed to be black so that it can trap sunlight and heat the ground underneath it. This heating up helps kill pests, weed, grass, and everything else below the sheet. To know if soil solarisation worked, you simply need to remove the sheet and watch if there is any sign of life in the area underneath it for a couple of days. After soil solarisation, you can add soil to your garden.
The other method of protecting your raised garden box from grass and weeds is to use a liner. In the next section, you will learn about the types of liners usually used on the bottom of raised garden beds and their pros and cons.
What should I put on the bottom of my raised garden bed?
Before you add soil to your raised garden bed, it is good practice to add a liner. This will help block weed and soil from affecting the plants you want to grow in your box. It will also help to block pests from penetrating your raised garden bed from below. Below are the materials commonly put on the bottom of raised garden beds before the addition of soil.
People frequently add newspapers or magazines to the bottom of their raised garden beds. While these don’t normally last for long because they decompose quickly, they are better than nothing.
Newspapers are perfect for garden beds constructed for fast-growing and maturing vegetables or plants. This is because they typically only prevent the growth of grass/weeds for a few months before decomposing.
The best thing about using newspapers is that when they decompose, they add a layer of nutrient-rich organic matter for the next plants.
Many experienced gardeners use cardboard as a liner in their raised garden beds. The best thing about cardboard is that it is tougher than newspapers.
In other words, it lasts longer on the bottom of raised garden beds when compared to newspapers. It, therefore, does a better job of protecting raised garden beds from grass, weeds, and pests. Like newspapers, cardboard also decomposes and adds humus to the soil.
Landscape fiber is considered by many to be the best material for putting on the bottom of raised garden beds. This is because it has many holes in it to allow aeration from the bottom and to make sure water-drainage is not affected.
The best thing about it is that it blocks grass and weed from growing through it and it can do this for up to ten years if not damaged by careless digging.
The second best thing about landscape fiber is the fact that it is eco-friendly. It is normally made from recycled materials.
The only problem with landscape fiber is that it cannot be tilled very deeply as this can destroy it and render it useless.
Some people use different kinds of plastic materials to line the bottom of their raised garden beds. Plastic materials are perfect grass, pest, and weed barriers especially if they are tough. Nevertheless, they have several drawbacks. First, most plastic materials are not water-permeable. This means they will hold water and prevent water from draining from raised garden beds.
When water does not drain from garden beds, the result is almost always waterlogging and root rot. To improve the permeability of plastics, people often create a few holes through them.
Second, plastic materials are toxic. They are toxic in the sense that they leach chemicals into the soil. While some plastics leach more than others, it is now known that all plastics leach chemicals. And the chemicals not only affect the environment but also the food grown. Nevertheless, it is important to note that some plastic materials leach less than others. These are the ones commonly used to make garden liners.
Concrete slabs are typically used by those building raised garden beds that they hope will last for a long time. They are perfect for gardens with very stubborn weeds or terrible soil. This is because they create a nice permanent barrier between the ground below and the raised beds.
Normally, when concrete slabs are used to line raised garden beds, holes must be drilled through them to improve drainage. Moreover, they are often only used for deep garden beds because this allows the addition of a thick layer of good soil that can sustain vegetables.
There are a couple of problems with using concrete slabs as raised garden bed liners. First, they are typically more expensive. Second, they normally increase soil pH making soil only suitable for certain crops. Lastly, they block root development for plants that normally have deep root systems.
Gopher wire is kind of like chicken wire but it is also at the same time not the same thing. Gopher wire is perfect for using to line garden beds in gardens where burrowing pests are a frequent menace. No burrowing pests can penetrate a well-set gopher wire. The only problem with the wire is that it does not keep grass and weeds out. Grass and weeds can grow straight through it.
The best thing about gopher wire is that it allows maximum drainage. This makes it perfect for use in garden beds designed for plants that prefer very efficient drainage.
Hardware cloth is sometimes used in the place of gopher wire by some gardeners. The biggest difference between gopher wire and hardware cloth is the size of the holes through them and the design.
The final words
You can line your raised garden bed with just about anything. If you are focused on growing safe food, you should use a cardboard box to line your raised garden bed. It will prevent weeds, grass, and pests. If you want something that will last for a very long time, you should go for landscape fabric, plastic, or concrete slabs. However, keep in mind that landscape fabrics and plastics are not very eco-friendly.