Laying turf looks simple on the surface, but what goes underneath it is often the difference between a lawn that thrives and one that struggles from day one. The base layer controls how water moves, how roots establish, and how smooth the finished surface looks months later.
Many homeowners focus on the turf itself and overlook the prep work below it. That mistake usually shows up as uneven settling, poor drainage, or turf that never fully takes hold. Getting the underlayer right sets the stage for everything that comes next.
If you're unsure what to put under turf before laying your sod or seed, we break down the proper base materials and preparation steps below.
What this article covers:
- What Type Of Turf Are You Laying?
- What To Put Under Real Turf (Sod) Before Laying
- What To Put Under Artificial Turf Before Laying
- Which Is Better: Natural Turf Or Artificial Turf?
What Type Of Turf Are You Laying?
Before you touch the soil, you need to be clear on the type of turf you are installing. Turf is a broad term, and understanding what is turf helps prevent confusion during prep.
Natural Turf (Sod Turfgrass)
Natural turf refers to real, living grass that is grown on farms and harvested in rolls or slabs. It includes varieties like Bermuda, zoysia, tall fescue, and St. Augustine.
Sod needs a healthy, living soil base so the roots can grow down into the ground quickly. Without that connection, the grass dries out, weakens, and fails.
Artificial Turf (Synthetic Lawn)
Artificial turf is a manufactured surface designed to look like grass. It's made from plastic or nylon fibers, so it relies entirely on a stable, compacted base for support. The goal under synthetic turf is drainage, leveling, and long-term stability, not plant health.
What To Put Under Real Turf (Sod) Before Laying
Start With Clean, Bare Soil
Remove all existing grass, weeds, roots, rocks, and debris. Sod installed over old turf or compacted patches struggles to make soil contact.
When sod is laid over debris, roots cannot penetrate evenly. That leads to dry spots, weak seams, and sod that lifts easily weeks later.
Add A Layer Of Quality Topsoil (If Needed)
Not every lawn needs added topsoil, but many do. You should consider topsoil if your existing soil is very thin or mostly clay.
In most cases, 1 to 3 inches of quality topsoil is enough to improve rooting and leveling without creating drainage issues. Spread it evenly and blend it lightly into the native soil below rather than leaving a sharp layer line.
Mix In Organic Matter For Better Rooting
Compost is one of the easiest ways to upgrade the soil under sod. It improves structure, moisture retention, and microbial activity.
Loose, workable soil matters more than depth alone. Sod roots establish fastest in soil that holds moisture without staying soggy. A light mix of compost helps achieve that balance.
This is also a good time to evaluate soil health. A basic soil test kit can identify nutrient gaps before the sod goes down, making early fertilization more precise.
Level And Grade The Area
The soil surface should be smooth and gently graded so water flows away from foundations, patios, and walkways. Fix low spots now. Once sod is installed, correcting dips becomes much harder without removing sections of turf.
Lightly Firm The Soil (Do Not Leave It Fluffy)
Overly loose soil settles after watering, which creates dips and uneven seams. Lightly firm the surface with your feet or a roller so it is stable but not compacted. The goal is a smooth, supportive base that still allows roots to grow downward quickly.
What To Put Under Artificial Turf Before Laying
Weed Barrier Fabric
Weed barrier fabric is often installed over native soil to reduce weed growth under synthetic turf. It can be helpful in areas with aggressive weeds.
However, in poorly drained sites, the fabric can slow water movement. Proper base material selection matters more than fabric alone.
Crushed Stone Or Decomposed Granite Base
A compactable base is critical for artificial turf. Crushed stone or decomposed granite creates a firm surface that resists shifting.
This layer supports drainage and prevents the turf from sinking over time. It should be installed in thin lifts and compacted thoroughly.
Sand Leveling Layer (Optional)
A thin sand layer is sometimes used to fine-tune leveling before turf installation. It helps smooth minor imperfections in the base. Sand should never be the primary structural layer. It works best as a final adjustment, not a foundation.
Edge Restraints And Proper Drainage Plan
Edge restraints keep artificial turf from creeping or separating. Proper drainage planning prevents water pooling after rain or irrigation. Skipping these steps often leads to visible movement and standing water issues.
Which Is Better: Natural Turf Or Artificial Turf?
Natural turf offers cooling, softness, and the ability to repair damaged areas over time. It also supports soil health and integrates seamlessly with the rest of the landscape. With proper prep and lawn fertilizer, real grass remains the best option for most home lawns.
Artificial turf can make sense in specific problem areas where grass will not grow, such as narrow shaded strips or pet runs. However, it lacks the temperature regulation, repairability, long-term flexibility, and can be harmful to the environment.
For most homeowners, natural turf from sod or grass seed remains the better long-term solution when installed over a properly prepared soil base. Understanding the types of turf available helps match the right option to the space rather than forcing a one-size-fits-all choice.
Conclusion
The success of any turf installation starts below the surface. Real grass needs clean, well-structured soil that supports fast rooting, while artificial turf depends on a compacted, well-drained base that stays stable over time.
Taking the time to prep correctly prevents uneven settling, drainage problems, and premature failure.
At Lawn Synergy, we help DIY homeowners get professional results by pairing smart preparation with the right products and timing.
Whether you are planning ahead with targeted lawn fertilizer, building a season-long plan through a lawn care subscription, or addressing soil structure with a quality soil conditioner, the right foundation and follow-through make all the difference.
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