Can you grow grass on concrete? Absolutely yes. In fact, it is the perfect way to make your yard look tidy and pleasant, giving you a glowing green lawn.
There is a multitude of reasons why you want to do this.
For instance, your old driveway might be an eyesore, or your patio could be calling for some sprucing up.
Is It Possible To Grow Grass Over Concrete?
Grass can grow over concrete, but it is certainly not an ideal medium. You’ll need a soil base over the concrete surface to hold the grassroots together.
Grass can also grow quickly if the surface is already cracked up. This is likely to happen over a long period.
However, the soil is vital for providing nutrients and moisture to your grass.
The next important thing is an efficient drainage system, for which you might want to drill some drainage holes. In fact, drainage is the first thing you want to work on before layering the concrete with soil.
Another good thing about concrete is its ability to hold water, owing to its high porosity.
What Are The Best Grasses To Grow On Concrete?
Not all grass types will have the same success rate when you grow them on concrete. Zoysia grass (a type of turfgrass) gives the best results with substantial growth because of its hardiness.
It has little fuss over maintenance once you lay it on the lawn.
Zoysia proliferates using vine like structures called stolons. It also has a well-developed root system.
Other grass types you can grow individually or together with Zoysia include
- St. Augustine Grass
- Centipede Grass
- Creeping Red Fescue
In a nutshell, you want a drought-tolerant grass species that has shallow roots.
Once you take care of the two main factors for growing grass on concrete; the drainage needs and the grass type, it’s time to get down to business.
Step 1: Clean Up The Concrete Space
Dirt and debris can impede new grass growth— you want to clean up the whole concrete space before laying the soil base.
Dirt is always a prerequisite for fungal diseases that harm your grass and soil.
The best tool for the cleaning exercise is a pressure washer that does a thorough job of removing dirt.
Step 2: Spread Topsoil
For your grass roots to grow and spread, you’ll need to lay about 4 inches of soil on top of the concrete base.
Ensure a well-leveled planting surface by adding more topsoil to low-lying spots.
Some gardeners opt for 6-7 inches of soil which is still ideal since it gives your grass more room to grow.
Step 3: Create A Slope
Your new seed bed on concrete needs a gradient to allow excess water flow. Standing water is highly undesirable since it provides a conducive ground for diseases and pests.
Your grass roots will also be prone to rotting.
Step 4: Spread Fertilizer Over The Topsoil
You want to jump-start your grass with starter fertilizer. It contains essential nutrients that make grass germinate at a fast rate.
Most commercial fertilizers have a user guide printed on the package to guide you on the application.
If you want to avoid fertilizer, compost manure will also do the trick.
Ensure you thoroughly mix the material with the topsoil before moving to the next step.
Step 5: Plant Grass Seeds
The next step is to plant your preferred grass seeds. You can broadcast the seeds using a mechanical spreader or by hand, depending on the lawn size.
Ensure you leave no patches on the surface by spreading the seeds vertically and horizontally.
You can divide your grass seeds into two parts. Spread the first part horizontally, followed by the second part, which is to be spread vertically.
We advise against planting too many seeds. This results in stiff competition for nutrients stifling growth.
Step 6: Rake
Rake the seeds after broadcasting. Do light raking to ensure the grass seeds are covered with about ¼ inch of soil.
Raking helps to keep birds from munching the seeds.
It also helps prevent the seeds from being washed down the slope through water run-off. Avoid deep raking since it hinders germination.
Step 7: Water The Grass Seeds
Once you’re done with raking, your next step would be to water the grass seeds. The best tool to use is a sprinkler which helps in distributing water evenly without pooling.
Avoid overwatering at all costs since concrete doesn’t provide the best drainage, and your seeds could rot before germinating.
While growing grass on concrete is doable, multiple problems could arise. This section highlights some challenges you’re likely to encounter.
1. Feeble And Dying Grass
Grass grown on concrete will likely succumb to summer heat due to a thin soil layer that cannot hold enough water and nutrients.
2. Water Clogging
Despite having numerous pores and holes, a concrete surface doesn’t offer sufficient drainage for your grass.
This leads to water clogging, resulting in root rot and premature death.
Excess still water above the soil also encourages numerous disease vectors and pests.
3. High Maintenance
In comparison to regular soil, grass grown on concrete requires high maintenance in terms of watering and fertilizer requirements.
You may want to look deeply at the above factors before deciding to go ahead with the planting.
Some Tips for Maintaining Grass Grown On Concrete
- Maintain a consistent watering schedule. Water the grass profoundly only when the bed is completely dry.
- Make sure that the grass is firmly established before going ahead with mowing. However, once established, keep it mowed at a few inches of height to make it continue growing stronger. Mowing also helps prevent the growth of weeds.
- Get rid of dead leaves and debris from the grass. They tend to decompose and promote the growth of troublesome micro-organisms and pathogens.
- Eradicate weeds to prevent them from competing for nutrients with your grass.
If you have an old walkway or an eyesore pavement in your yard, use the guide above to spruce it up with grass cover.
Fundamentally, ensure your lawn has sufficient gradient to allow excess water to flow away since concrete doesn’t provide enough drainage.
Additionally, have a sufficiently thick layer of soil for the best results.
Job Kiniale is a certified crop scientist and gardening enthusiast with a passion to help beginning gardeners navigate their newfound hobby. Let’s talk about plants, backyard ideas, and general gardening advice. Outside work, Job loves spending time with family.