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Can you put soil on top of concrete? Initially, I assumed it was simple, but the reality proved otherwise. Hence, this post details the process of placing soil on concrete, addressing key considerations along the way.
Although concrete isn’t an ideal surface for putting soil on, it can be used for soil. At least four inches of topsoil must be placed over concrete for grass to grow from the soil successfully. Make sure that the area is well maintained, and fertilizers are sprinkled.
In the next sections, we will discuss just how to place soil over concrete, alternatives to doing this, and how putting soil on concrete affects plant and root growth, so please read on!
Things to consider when putting soil on top of concrete
If you intend to lay grass on the soil, drainage is vital to ensuring the grass can grow on top of the concrete. Water collects and prevents oxygen from getting into the soil without adequate drainage. This will ultimately result in the grass or other plants dying out.
Look into proper drainage measures when putting soil on top of concrete
This can be avoided if correct drainage measures are taken. Drainage grooves are a great way to drain water from the concrete. The ideal time to form these grooves is before the concrete dries, but this can also be achieved when hardened by using a mortar and concrete saw that a professional should perform.
Look into raised bed gardening before putting soil on top of concrete
If creating drainage is impossible or sounds too strenuous, another option is to create a raised garden bed on concrete.
As previously stated, the heat absorption of concrete can hinder the growth of grass or plants in the soil, particularly in the hot summer months.
A raised bed separates the soil and the concrete, allowing for more soil depth to be laid. The deeper the soil, the easier it is for plants and grass to get nutrients and survive in the long term.
Raised Beds on Concrete
Raised garden beds make growing possible for everyone with a small land area. They are a great way to turn small patches of concrete or pavement into thriving gardens. Building raised beds are straightforward and requires some basic joinery skills.
Here’s a list of the main benefits of raised beds:
|Improved water retention||Improved drainage|
|Increased growing space||Prevention of soil erosion|
|The soil on top of the concrete remains warm |
but not too hot for growth
Raised beds allow more soil to be put on top of the concrete, increasing the chances that anything planted in the soil will survive.
Four inches is the minimum depth of soil required for raised bed gardening, but it would be better to have twelve inches if possible. This depth would be more than enough soil to grow on. Basically, the deeper you can make the soil, the better chance of things growing from it.
How to make a raised garden bed
Firstly it is important to measure the concrete area correctly and get enough wood to construct a bed that will cover the desired patch. The raised bed needs to be sturdy enough to withstand the weather.
Sizing and content considerations for a raised garden bed
When the bed has been built to the desired size and depth, filling the bottom with a layer of leaves, grass clippings, wood chips, straw, and other organic materials is good. Then add a layer of cardboard on top.
When the soil is added, the mixture will begin to break down over time, turning into rich compost for a thriving raised bed.
To aid you in having a clearer picture of this process, feel free to look into my recent article on just what raised bed gardening is. This article contains the rundown on the recommended soil types and ratios that you should use for raised bed gardening, the number of beds you can consider making, and how to tend and harvest in this gardening method.
Drainage considerations for a raised garden bed
You should make sure that the beds can drain. Otherwise, the soil may become waterlogged, causing the plant’s roots to drown.
Using wood chippings when putting soil on concrete
Wood chippings are also useful when putting soil on top of concrete.
The chippings can be spread to layer and build up the soil, creating more space between the topsoil and the concrete and preventing too much heat from causing damage to whatever is being grown in the soil.
Can You Put Sod on Top of Concrete
If you have concrete areas in your garden, they can appear unsightly, so understandably, you want to cover them in vibrant grass. The minimum soil depth for grass over concrete is around 12 inches.
When considering how to landscape over concrete you should think about ways to break up the concrete, thhis will help drainage and allow root systems to penetrate the concrete. A small jackhammer, or sledge hammer will be the tool of choice for this job.
Have a good amount of topsoil before growing grass on concrete
Thankfully, although growing grass over concrete is not easy, it is still achievable if you have the proper amount of topsoil. The level of drainage will also greatly impact the growth of the grass. Large concrete areas are liable to pool with water, making it impossible for the grass to get the amount of oxygen it needs to survive.
New houses and lawns
During the construction of new houses, contractors often dispose of rubble and concrete in the back yards of the property. This is why when you dig into a new lawn to plant a tree you will often find concrete under lawn
This rubble is a way for the housing contractor to save on the production of the house, cutting down skip costs. It also answers the question can you lay real grass on concrete? Most of our gardens will have concrete under the lawn.
It is best to plant low maintenance and grow almost anywhere – like Creeping Red Fescue on top of concrete.
Applying an even amount of seed to the soil on top of the concrete is essential as this will allow the nutrients to be shared amongst the grass and prevent it from competing.
Can you put soil on top of concrete when creating a green roof?
Can you put soil on top of concrete to create a green roof space? Absolutely! By carefully preparing the concrete surface, adding a layer of appropriate soil, and selecting suitable plant species, you can transform a lifeless concrete area into a thriving green oasis. It can enhance sustainability, biodiversity, and aesthetic appeal by putting soil on top of concrete for a vibrant green roof experience.
A study performed by Springerlink showed that although natural soil can be used on concrete to create a green space, it caused a weight issue and other non soil products are better to use. However, it showed that placing soil on top of a concrete driveway or patio has no known adverse affect.
How the depth of soil affects its ability to grow
If you intend to grow a variety of plants, vegetables, and shrubs on the soiled concrete area, the depth of the soil is probably the most influential factor in whether this will be successful.
If the soil is too shallow, it will be difficult for plants to get the necessary nutrients into their roots. Increasing the depth of the soil allows for these nutrients and moisture to be shared more evenly.
Recommended soil depth for planting on top of concrete
So when considering can you put soil on top of concrete to grow salads and herbs, the depth is a crucial factor, a depth of at least twelve inches is necessary.
Other vegetables may require more than the foot soil depth to ensure their roots are kept healthy and minimize the amount of watering you will be required to do.
Raised beds are, without a doubt, the best solution to the problem of soil depth. Beds allow you to control the depth and make the most of the space in your garden. They can also be a fun design project if you enjoy woodwork.
Alternatives to putting soil on concrete
The next few sections will examine what one can look into instead of potting soil on concrete.
Use artificial grass or turf.
I appreciate that for some people, putting soil on top of concrete may be to make your garden more visually pleasing rather than to grow plants on. If this is the case, artificial grass is something worth considering.
Putting soil on top of concrete and successfully growing grass is not easy, so artificial grass provides a time-saving alternative.
A shock pad is installed over the concrete to soften the surface and smooth any imperfections. Holes are drilled through the concrete for drainage, and the turf is installed.
Artificial turf and grass considerations
This isn’t suitable for gardeners out there, but for purely aesthetic reasons, artificial turf can improve the look of your garden in a matter of hours.
There are cheap and expensive options out there, so it is important to research and ensure you get the right turf for your garden.
Drainage of artificial turfs
Along with the pleasantness, most people also have qualms about just how well artificial grass allows for water drainage, comes rains, or watering of plants above said artificial grass.
To aid you with this, I have written an article on just how well artificial grass drains since this is one of the largest considerations. It also covers information about maximizing your artificial grass and a list of artificial grass variants you can look into.
Can you put topsoil over gravel?
the minimum soil depth for grass over gravel would be 4-6 inches depth would be recommended for a lawn on top of the gravel. As for vegetable gardening, it is better to opt for at least 8-10 inches of soil.
How do you break up concrete?
Breaking up concrete by hand is possible with a sledgehammer. Sprinkle the concrete with water. Hold the hammer close to the head while keeping the other hand at the handle’s end. Lift it high but not over your head, and bring it down on the concrete until it is sufficiently broken.
Can you make a flower bed on concrete?
You can make a flower bed on concrete through raised bed gardening. Ensure to custom-build the raised garden bed to your plant needs and think of a proper soil depth for the bed. With the raised garden bed material, look into utilizing concrete blocks aside from the usual wood bed material.
Can plants grow through concrete?
When looked through a microscopic lens, cracks are present in concrete. These will be sought out by the plant roots as they grow, as they can look for the easiest path of more growth and space. The roots will stick through the crevices and, as it grows, effectively crack through it.
Why is there concrete under my lawn?
Concrete may be unearthed in our backyards. This may be builders’ fill, concrete from past projects of builders that they have placed in your soil, which is cruel and unfortunate. An excess of this is detrimental to plant growth, especially if it outright blocks the whole of your lawn.
Conclusion on can you put soil on top of concrete
Regarding can you put soil on top of concrete, one common obstacle you might face is that the concrete can get hot in summer due to its thermal mass. This isn’t a problem in the winter, as the concrete’s warmth will benefit the soil and any plants or grass.
A solution to the problem of the concrete getting too hot is to raise a bed before putting the soil on top of the concrete. This will prevent roots and soil from being damaged by heat. This information and all covered in this article should hopefully give you insight into what you can do with concrete and gardening.
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