- Naomi Stephens | Permaculture Designer
Raised Beds on Concrete: A Step-by-Step
Updated: 4 days ago
Do you have a concrete patio or driveway that you're not quite sure what to do with? You could just leave it as is, but if you're looking for a way to add some life and color to your outdoor space, consider creating raised beds on concrete.
Raised beds on concrete are a great way to grow food in a small space. In this blog article, I'll be covering 5 steps to growing raised beds as well as frequently asked questions.
In this article:
Step 2: Preparing the Concrete
Step 3: The best-raised beds to choose for Concrete
Step 4: Adding Drainage, Soil, and Plants
Step 5: Caring for your raised bed garden
Step 1: Choose Your Plants
When you choose plants for your garden, it is important to consider the amount of sunlight and water they will need. If you are gardening on concrete, you may not have a lot of space for large plants.
Instead, opt for smaller varieties that can be grown in containers. Some good choices for container gardens include herbs, succulents, and dwarf vegetables.
You should also consider the amount of maintenance required for each type of plant. For example, herbs generally require less watering than other types of plants.
The best edible plants for raised gardening beds are:
- herbs (basil, oregano, thyme, mint)
These are the best edible plants for raised beds on concrete because they are all small in size and require little maintenance.
Succulents are also relatively low-maintenance, but they will need more sun than most other types of plants. Once you have selected the plants for your garden, it is time to move on to step two: preparing the concrete.
Step 2: Preparing the Concrete
Before you can start raised bed gardening on concrete, you need to prepare the concrete surface. First, remove any loose debris or dirt from the surface.
Next, use a garden hose or pressure washer to clean the concrete. If there are any cracks or holes in the concrete, fill them in with a patching compound.
Once the surface is clean and smooth, you're ready to start building your raised bed garden.
Step 3: Choosing your raised beds for concrete
The best-raised beds for concrete are sturdy and made of weather-resistant materials like cedar, metal or recycled plastic.
Cedar Raised Beds
Cedar is a popular choice for raised garden beds because it is naturally rot-resistant and durable. This makes it an ideal material for raised garden beds placed directly on concrete, as it will not break down over time. Cedar also has a beautiful grain pattern and natural coloration that can add character to your outdoor space. However, cedar can be more expensive than other materials, such as pressure-treated lumber. And because it is a softwood, it is also more prone to damage from impact or pets. Overall, cedar is a good choice for raised garden beds on concrete.
There are a few highly recommended cedar raised beds that are available on Amazon:
Boldly Growing has a 4x 4 Cedar rot-resistant raised bed, which is available as a single or double raised bed. This product out competes most on the market in its range because of the following:
It's a great raised bed for gardening edible varieties specifically because 11" height is sufficient for adequate root growth.
It has a better build system, meaning you can build it in just 3 simple steps. The holes are pre-drilled making your life so much easier. Most people comment that it takes them less than 20 minutes to build.
It's safe to be around kids or pets as they make sure the boards are properly sanded and are without splinters.
They use raw untreated cedar which means no toxic materials are going to be leached into your garden bed.
There is attention to detail in the grooves and carpentry making it look stylish in your garden.
They provide a 1 year warranty
Boldy Growing raised bed has very positive reviews with people noting that it survives harsh weather such as snow, rain and wind without any signs of cracks or strain.
Click on the slide show below
At the time of writing this product cost $99 for a 4x4 on Amazon
Plastic raised beds
There are several reasons why plastic is often chosen as the material for raised beds on concrete. One of the main advantages of plastic is its durability. Unlike wood, which can rot or be damaged by termites, plastic beds will last for many years with minimal maintenance. In addition, plastic is much lighter than wood, making it easier to move and position. Another advantage of plastic is that it doesn't require any special treatment or sealing, as concrete can sometimes do. Finally, plastic beds are often much less expensive than wood or metal beds.
However, there are also some disadvantages to using plastic for raised beds. One of the main drawbacks is that plastic can get very hot in direct sunlight, which can damage plants. In addition, plastic is not as strong as other materials and can be easily damaged if it is not handled carefully. Despite these disadvantages, plastic remains a popular choice for many gardeners due to its many advantages.
Victory 8 Garden has a 4x4 highly convenient plastic raised beds which saves a lot of hassle and is a lot cheaper than other options. They also have a wide range of sizes. It's a highly recommended option for a plastic raised bed because:
It has no DIY assembly
It's a good depth for growing root vegetables at 11.5"
It's made of Aeroflow, meaning it's specifically designed allow air flow.
It's currently more popular than the above cedar raised bed as its more because its a reliably easy product to use and is both durable and weather resistent. It's also beneficial for people who only have a small limited to space to grow for example on their balcony.
At the time of writing it's currently on sale at $49.97, it was originally listed at $79.95
Metal raised beds
There are many benefits to using metal raised beds on concrete. For one, metal is a durable material that will last for many years. It's also easy to clean and maintain. Additionally, metal raised beds can help to control the temperature of the soil, which is important in hot climates.
However, there are also some drawbacks to using metal raised beds on concrete. One downside is that they can be quite expensive. Additionally, they can get very hot in direct sunlight, which can damage delicate plants.
Land Guard has a best-selling highly reviewed 4×2×1ft ,7.14Cu metal raised bed. It's a great choice for raised beds on concrete because it's easy to set up, has an open base, and is thicker than your average metal raised beds reaching 1.56mm in thickness.
It comes with extra nuts and bolts, many people comment that it is quite sturdy and it allows for creativity i.e if you buy two sizes you can mix and match how you put them together.
However as the instructions warn it does have sharp edges, so if you have kids around then be extra careful or perhaps consider a wooden or plastic raised bed.
At the time of writing it's currently on sale at $59.99, it was originally listed at $79.99
Step 4: Adding Drainage, Soil and Plants
Start filling up your raised bed by adding a filler material such as gravel, sand, or soil can be added to the bottom of the raised bed to help with drainage. You can also add a layer of fabric or plastic lining to the bottom of the bed to help prevent weeds from growing up through the concrete. It will also stop the liquid from leaching onto the concrete. Whatever you choose, make sure it is something that will not block the drainage holes in your raised bed.
Now that you have your drainage set up, it's time to add soil and plants! If you are using a pre-made mix, simply follow the instructions on the bag. If you are making your own mix, start with a layer of organic matter such as compost or leaves. Add a layer of topsoil, and then mix in some sand or other amendments to improve drainage. Once your bed is filled with soil, it's time to start planting.
If you are growing vegetables, choose varieties that are well suited to your climate and soil type. Be sure to space plants according to their mature size, and give them enough room to spread their roots. With a little care and attention, your raised bed garden will soon be bursting with life!
Step 5: Caring for Your Raised Bed Garden
Assuming you have followed all the steps up to this point, you should now have a beautiful raised garden bed full of healthy plants. But how do you care for a raised garden on concrete? The key is to make sure the bed stays moist, but not too wet. Water in the morning so the leaves have time to dry off before nightfall.
If it is especially hot or windy, you may need to water more than once a day. You can use a hose with a sprinkler attachment, or install a drip irrigation system. When it comes to fertilizing, less is more. too much fertilizer can burn your plants. Apply a fertilizer made for vegetables once a month, or follow the directions on the package.
As your plants grow, you may need to stake them or add supports to keep them from toppling over. Just be careful not to damage the roots when you are adding supports. With a little care, your raised garden on concrete will provide you with fresh vegetables all season long!
Can you use galvanized steel to build raised beds?
You can certainly build raised beds out of wood, stone, or concrete blocks, one material you may not have considered is galvanized steel. Galvanized steel is extremely durable and will last for many years with proper care. It's also relatively inexpensive and easy to find. One downside of using galvanized steel for raised beds is that it can be difficult to cut and shape. However, many hardware stores now carry pre-cut panels that make it much easier to get started.
How do I create drainage in raised beds?
Drainage is an important consideration for raised garden beds. Poor drainage can lead to plant roots sitting in water, which can lead to root rot and other problems. There are a few different ways to improve drainage in raised beds. One is to add a layer of coarse gravel to the bottom of the bed before adding soil to help the water drain faster.
Another is to make sure that the bed is elevated at least six inches off the ground, which will help water to drain away from the roots. Finally, it's important to choose a soil mix that includes perlite or sand, which will help water to drain more quickly. By following these tips, you can ensure that your raised garden beds have good drainage and healthy plants.