Laying Artificial Grass on Grass? A Pro's Unflinching Guide

The Big Question: Can You Lay Artificial Grass Directly on Grass?

It’s the question our team at Modern Yardz gets all the time. It seems so logical, so simple. You have grass, you want artificial grass, so why not just roll the new stuff out over the old? A quick cover-up. We get the appeal—it sounds like a fantastic shortcut that saves time, money, and a whole lot of sweat. But here’s the unflinching truth from a team that has installed thousands of square feet of turf across San Diego: laying artificial grass directly on top of natural grass is one of the biggest, most catastrophic mistakes you can make. It’s a recipe for failure.

Honestly, it’s a shortcut that leads directly to a lumpy, foul-smelling, weed-infested mess that you’ll have to tear out and redo in a year or two. The organic material underneath—the grass, the roots, the soil—will begin to decompose. It won't happen evenly. This creates soft spots and hard spots, turning your once-smooth lawn into a miniature, lumpy moonscape. Worse yet, that decomposition can trap moisture, leading to mold, mildew, and a persistent, unpleasant odor. And the original grass? It won't just die gracefully. Hardy weeds and stubborn blades of grass will fight their way through the drainage holes of your new turf, creating a maintenance nightmare you were trying to avoid in the first place. This isn't a foundation; it's a ticking time bomb. Our professional advice—and we can't stress this enough—is to never, ever do it. The real secret to a perfect artificial lawn isn't the turf itself; it's the meticulous preparation that happens underneath.

The Modern Yardz Method: A Foundation for Lasting Beauty

So, if the shortcut is out, what’s the right way? The right way is about building a proper foundation—a stable, well-draining, and completely inorganic base that will support your lawn for the next 15-20 years. This is the method we've refined over countless projects, from cozy backyards in Chula Vista to sprawling landscapes in Oceanside. It’s not just about how to lay artificial grass on grass; it’s about how to replace natural grass with a superior, engineered system. It takes work, yes, but the result is an impeccable, evergreen lawn that looks and feels incredible year after year. Let’s break down the process.

Step 1: Planning and Measurement - The Blueprint for Success

Before a single shovel hits the dirt, you need a plan. This is the architectural phase of your lawn project. Grab a tape measure, a notepad, and maybe a cup of coffee, and get outside. Measure the area you intend to cover and sketch it out, noting the dimensions. Calculate the total square footage (length times width) to determine how much turf, base material, and infill you'll need. We always recommend adding 10-15% extra to your turf order to account for cuts, angles, and any potential mistakes. Running out of material mid-project is a formidable headache you don't need.

But planning goes beyond just numbers. Think about how you’ll use the space. Is it a high-traffic play area for kids and dogs? A pristine, decorative space for entertaining? The type of turf you choose will depend on this. Now for a pro tip that makes a huge difference: consider the grain direction. The blades of artificial turf all lean slightly in one direction, which affects how the light hits it. For the most natural look, you want the grain of the turf pointing toward the main viewing area, like your patio or kitchen window. Make a note of this on your sketch—it’s a critical, non-negotiable element for a professional-looking finish.

Step 2: Clearing the Canvas - Removing the Old Lawn

This is the part that requires the most muscle, but it’s absolutely imperative. The entire existing lawn, including the top layer of soil and root system, has to go. You’re aiming to excavate down about 3 to 4 inches across the entire area. For smaller spaces, a good old-fashioned shovel and wheelbarrow will do the trick. For larger lawns, we strongly recommend renting a sod cutter from a local hardware store. It will save your back and an enormous amount of time.

Why 3-4 inches? Because that depth gives you enough room to build a robust, stable sub-base that won’t heave or sink over time. It ensures you’ve removed the vast majority of the organic material and weed seeds that could cause problems later. Once the old sod is gone, you should grade the area. This means raking it smooth and creating a very slight, almost imperceptible slope—about a 1-2% grade—that directs water away from your home's foundation and toward a designated drainage area. Proper drainage starts here, at the most fundamental level. Many of the issues we're called in to fix stem from this step being rushed or skipped entirely.

Step 3: Creating an Unflinching Base - The Sub-Base Installation

Welcome to the most important step in the entire process. The sub-base is the unsung hero of every great artificial grass installation. It provides the stability, durability, and—most importantly—the drainage your new lawn needs to perform flawlessly. Skipping or skimping here is not an option.

Our team in San Diego almost exclusively uses a material called Crushed Miscellaneous Base (CMB) or a similar Class II road base. It’s a mix of sand and small, angular stones that, when compacted, lock together to form an incredibly solid yet porous foundation. You'll need to spread this material evenly across the excavated area to a depth of about 3 inches. Use a wheelbarrow to dump piles and a landscape rake to spread it out. You’ll want to get it as level as possible by eye, but don't obsess over perfection just yet.

Now for the part that separates the amateurs from the pros: compaction. You must, must, must compact the sub-base. We use a heavy-duty plate compactor for this, which you can rent. Starting at the outer edges and working your way in a spiral pattern, go over the entire surface at least two or three times. You'll then want to lightly spray the base with a hose (don't saturate it) and compact it again. This process settles the fine particles and locks the base into a rock-solid layer. A properly compacted base shouldn't leave a footprint when you walk on it. That’s the key. It’s this solid foundation that prevents dips, lumps, and sinking for years to come.

The Nitty-Gritty of a Flawless Installation

With the heavy lifting of the foundation complete, you're ready to move on to the more detailed work of actually laying the turf system. This is where precision and patience become your most valuable tools. The base is your canvas, and now it's time to create the masterpiece.

Step 4: The Weed Barrier - Your First Line of Defense

Even with a deep, inorganic base, some tenacious weeds can find a way. That's why we install a professional-grade geotextile weed barrier over the entire compacted base. This isn't your flimsy garden-variety plastic sheeting. We use a permeable fabric that allows water to pass through freely but physically blocks weeds from growing up from below. Roll out the fabric, making sure to overlap any seams by at least 6 inches to prevent any gaps. Secure the barrier using 6-inch landscaping staples or nails, especially around the perimeter and along the seams, to ensure it stays flat and doesn't shift during the turf installation.

Step 5: Rolling Out the Green Carpet

Now for the exciting part. Carefully move your rolls of artificial grass into position on top of the weed barrier. It's often helpful to unroll it next to the area first and let it relax in the sun for an hour or two. This helps release any stiffness from being rolled up and makes it easier to work with. When you’re ready, position the first piece along a straight edge, like a driveway or patio, leaving a couple of inches of overhang that you'll trim later.

Remember your plan and the grain direction? This is where it comes into play. Make absolutely certain that every piece of turf you lay down has the grain running in the same direction. If you mix them up, you’ll end up with a lawn that looks like a checkerboard of different shades of green. It’s a jarring and irreversible mistake. As you unroll the turf, be careful not to drag it across your perfectly prepared base. Walk on the turf itself as you position it to avoid creating any divots or imperfections in the surface below.

How to Install Fake Grass with DaznDi (Steps to Install Fake Grass)

This video provides valuable insights into how to lay artificial grass on grass, covering key concepts and practical tips that complement the information in this guide. The visual demonstration helps clarify complex topics and gives you a real-world perspective on implementation.

Step 6: Seaming - The Art of Invisibility

If there’s one step that screams “DIY job,” it’s bad seams. Making two pieces of turf join together into one invisible, continuous lawn is an art form. Our experience shows this is where patience and precision pay off dramatically. First, lay your two pieces of turf side-by-side, with the edges just touching. You’ll notice that both pieces have a factory edge, or a stitch row, running down the side. You need to trim this off. Using a sharp utility knife and a straight edge, carefully trim about two or three stitch rows off the edge of both pieces you intend to join. This allows the turf blades to mesh together naturally.

Once trimmed, push the two pieces together so they are snug but not overlapping. You shouldn't be able to see the backing, but the blades shouldn't be crushed against each other either. Fold back the edges of both pieces and lay down a roll of seaming tape (it's a special fabric, not an adhesive tape) directly on the base, centered under the gap. Then, using a trowel, apply a generous, zig-zag bead of turf adhesive along the entire length of the seaming tape. Carefully fold the turf edges back down onto the glue-covered tape, pressing firmly to ensure good contact. Be careful not to let any adhesive ooze up onto the grass fibers. After it’s set, the seam should be virtually invisible.

Choosing Your Infill: A Quick Comparison

The infill you choose does more than just hold the turf down. It supports the blades, adds ballast, and can even help keep the surface cool and odor-free. Here’s a breakdown of common options our team considers for projects:

Finishing Touches That Make All the Difference

Your lawn is laid, the seams are set, but the job isn't done yet. These final steps are what transform a good installation into a great one, giving your new lawn that professionally finished look that will make your neighbors green with envy.

Step 7: Securing the Perimeter

To prevent the edges of your turf from lifting over time, you need to secure the entire perimeter. Using 6-inch galvanized landscaping nails, hammer them in every 6 to 8 inches around the outside edge of your turf installation. Be careful not to hammer them in so far that you create a divot. The goal is to drive them just below the surface so the grass blades hide the nail head completely. A neat trick is to use your fingers to separate the grass fibers around the nail head before the final hammer strike. If your turf meets a hardscape edge like a concrete patio or walkway, you can use a wonder bar or a blunt chisel to neatly tuck the edge of the turf into the gap for a super clean, professional finish.

Step 8: The Infill - More Than Just Sand

As we covered in the table, infill is a critical component. It provides weight to hold the turf down, helps protect the backing from UV rays, and gives the grass blades the support they need to stand up straight. For most residential lawns, especially here in sunny San Diego, we recommend a high-quality silica sand or, if you have pets, an odor-absorbing option like ZeoFill. The amount you need depends on the pile height of your turf, but a good rule of thumb is about 1.5 to 2.5 pounds per square foot. The best way to apply it is with a broadcast or drop spreader, which ensures an even distribution across the entire lawn. Don't just dump it in piles—that will lead to an uneven finish.

Step 9: Power Brushing - Bringing it to Life

This is the final, magical step. After spreading the infill, you need to work it down into the base of the turf fibers. The best tool for this job is a power broom. This specialized machine has a stiff-bristled rotating brush that flicks the grass blades upright and forces the infill down deep into the thatch layer. You should brush against the grain of the turf to get the blades to stand up as tall as possible. If you don't have a power broom, a stiff-bristled push broom and a lot of elbow grease can work, but the results from a power broom are dramatically better. Once you’re done, your lawn will look lush, full, and incredibly realistic.

Why a Professional Installation Matters

As you can see, the process of how to lay artificial grass on grass is actually a process of complete replacement and reconstruction. It’s detailed, physically demanding, and requires a host of specialized tools and knowledge to get right. While it's certainly possible as a DIY project, the difference between a homeowner's attempt and a professional installation is often stark and immediately visible in the seams, the edges, and the overall flatness of the lawn.

Our team at Modern Yardz has the experience, the commercial-grade equipment, and the nuanced understanding of San Diego's specific soil and climate conditions to guarantee a flawless result. We handle everything from the initial design to the final power brushing, ensuring every layer of your new lawn is built to last. Our comprehensive landscape design Services go far beyond just turf; we create entire outdoor environments. We believe in building things the right way, once. You can learn more About our company's commitment to quality and see why so many homeowners trust us with their vision.

An investment in professionally installed artificial grass is an investment in years of hassle-free enjoyment. It's about reclaiming your weekends from mowing and watering, saving a significant amount on your water bill, and having a perfect green space ready for your family at a moment's notice. If you're considering making the switch and want to ensure it's done perfectly, our team would be happy to help you explore the possibilities. Feel free to Contact us for a consultation.

The appeal of a perfect lawn is universal, and with modern artificial turf, it's more achievable than ever before. But that perfection isn't achieved with shortcuts. It’s built on a solid, meticulously prepared foundation that will stand the test of time, traffic, and weather. It’s about doing the hard work upfront so you can relax and enjoy the stunning, maintenance-free results for decades. For a full look at our projects and philosophy, you can always visit our Home page. A great lawn isn't just laid—it's engineered from the ground up.