If you’ve ever battled stubborn weeds in your garden or flower beds, you know how frustrating it can be to maintain a clean, weed-free landscape. Landscape fabric is a popular solution, acting as a physical barrier between the soil and the surface mulch. But on its own, landscape fabric isn’t always foolproof. For more effective, long-term weed control, it’s smart to add extra layers under the fabric.

Let’s dive into what you can put underneath landscape fabric to boost your weed protection and improve the longevity of your landscaping.

Why Add a Layer Under Landscape Fabric?

Landscape fabric is designed to block sunlight (which weeds need to grow) while allowing water and air to pass through. However, aggressive or deep-rooted weeds like Bermuda grass, bindweed, or even tree seedlings can sometimes poke through the fabric over time—especially if the material deteriorates or is not properly installed. By placing certain materials underneath the fabric, you create an additional defense line that can:

• Block persistent weed roots
• Prevent fabric from tearing over time
• Improve drainage and soil health
• Reduce maintenance in high-traffic or high-growth areas

Boost weed control with the best materials to put under landscape fabric. Get expert tips for a cleaner, longer-lasting garden bed.

Top Materials to Put Under Landscape Fabric

1. Cardboard or Newspaper

• Why Use It: Biodegradable and effective at smothering weeds. Cardboard adds a solid layer of protection, especially against tough weeds.
• How to Use: Lay down flattened cardboard or several layers of newspaper directly over the soil. Wet them slightly to keep them in place, then install your landscape fabric on top.
• Pros: Eco-friendly, cost-effective, improves soil as it breaks down.
• Cons: Will eventually decompose (which is also a plus, depending on your goals).

2. Pre-Emergent Herbicide

• Why Use It: Prevents weed seeds from germinating in the soil below the fabric.
• How to Use: Apply directly to the soil following the manufacturer’s instructions before laying the fabric.
• Pros: Chemical-level protection that stops weed growth early.
• Cons: Not organic; may affect nearby plants if not used carefully.

3. Gravel or Crushed Stone

• Why Use It: Adds weight, helps with drainage, and discourages weed growth.
• How to Use: Spread a 1–2 inch layer of gravel or crushed stone before placing the fabric.
• Pros: Durable, long-lasting, excellent for areas where drainage is key.
• Cons: Can make planting or reworking the soil more difficult.

4. Plastic Sheeting (for non-plant areas)

• Why Use It: Completely blocks moisture and light, preventing any weed growth.
• How to Use: Use in pathways or non-plant zones, then lay landscape fabric over it to improve appearance and durability.
• Pros: Absolute weed prevention.
• Cons: Prevents water and air movement—bad for plant health. Only use in areas with no vegetation.

5. Compost or Soil Conditioner

• Why Use It: Not necessarily for weed prevention directly, but can be a helpful pre-layer if you’re looking to build a healthy base that discourages invasive plants.
• How to Use: Apply a thin layer over the soil, then place fabric and mulch.
• Pros: Improves soil health, boosts plant resilience.
• Cons: May actually encourage some weeds if not covered properly.

How to Choose the Right Landscape Fabric?

Choosing the right landscape fabric depends on your specific gardening needs and the area you’re covering. Here are some key factors to consider:

1. Material Quality:Look for durable, UV-resistant fabrics that won’t degrade quickly in sunlight. Polyester or polypropylene fabrics are common choices.
2. Permeability:Decide if you want a permeable fabric that allows water, air, and nutrients to pass through (best for most gardens) or a more opaque fabric that blocks everything (for weed barriers).
3. Weed Suppression Strength:Thicker fabrics (about 3-5 ounces per square yard) generally provide better weed suppression but might be less permeable.
4. Ease of Installation:Choose a fabric that is easy to cut and handle, especially for irregularly shaped beds.
5. Compatibility with Mulch:Ensure the fabric works well with your chosen mulch—some fabrics are better suited for use under gravel, bark, or decorative stones.
6. Cost and Longevity:Higher-quality fabrics might be more expensive but last longer, providing better value over time.

Bonus Tips for Maximum Weed Control

• Overlap the Fabric: Always overlap fabric edges by at least 6–12 inches to prevent gaps.
• Secure with Landscape Staples or Pins: Use landscape staples to keep the fabric firmly in place, especially in windy or sloped areas.
• Use Mulch Wisely: Apply 2–3 inches of organic mulch over the fabric. This adds weight, improves appearance, and breaks down slowly to enrich the soil.
• Check Edges Regularly: Most weeds creep in from the edges, so reinforce borders with stone, edging, or extra layers.

Final Thoughts

Putting something under your landscape fabric is like giving your garden a head start in the never-ending fight against weeds. Whether you choose cardboard, gravel, or herbicide, the right combination can make a huge difference in how well your landscape holds up over time. With thoughtful preparation, you’ll spend less time pulling weeds—and more time enjoying your beautiful outdoor space.