What's the minimum soil depth for grass over concrete?

Concrete isn’t an ideal foundation for real turf. However, if you decide to go ahead without removing it, you’re likely wondering what the minimum soil depth is for grass over concrete.

Concrete isn’t an ideal foundation for real turf. In an ideal world, you’d be better off removing your concrete before laying your grass, as this will be better for drainage and the overall health of your lawn. However, if you do decide to go ahead with your concrete in place, you’re likely wondering what the minimum soil depth is for grass over concrete.

What’s the minimum soil depth for grass over concrete?

Grass roots can grow up to 6 inches long. So, you’ll need six inches of soil over your concrete as a bare minimum.

That said, in order for your grass to stand the best possible chance of thriving in this somewhat inhospitable environment, we’d recommend adding at least 10 inches of soil over your concrete.

Even then, you should choose a shallow-rooted species of grass as the roots search for nutrients and water deep down in the soil.

Other considerations for laying grass over concrete

Laying grass over concrete certainly comes with some added upkeep. Here are some things you’ll need to bear in mind to make it work.

Drainage

Grass needs good drainage in order to thrive. Otherwise, stagnant water will stop oxygen from being able to enter the soil, and your grass will die out quickly.

In order to ensure adequate drainage, you’re best off breaking up your cement base – or at least drilling several holes in it (around every foot).

Watering

In a shallow patch of soil like this, water will evaporate really quickly. This can be a problem on warm sunny days.

In hot spells, you’ll need to water your grass at least daily in order to give it the best chance of surviving.

Fertiliser

If you’re turfing over a concrete base, your grass won’t be able to feed off the soil’s nutrients in the same way.

For this reason, you’ll need to use fertiliser to feed your grass and keep it healthy.

Alternatives to laying grass over concrete

If you’re set on keeping your concrete in place, an alternative to laying grass over concrete is to use artificial turf.

Although it won’t give you the same aesthetic as real turf, it will improve the look of your garden within just hours. Plus, it won’t come with even a fraction of the maintenance and upkeep of laying real grass over concrete.

Get the help of a professional

Whatever approach you decide to take with your garden, getting the help of a professional can make all the difference between success and failure!

Call in a landscaper to turn your garden into a green oasis that you can get the best out of.