A root mat is a dense network of plant roots that stabilises soil, and the term also refers to matting products that protect or control root growth.

Whether you are dealing with erosion on a steep embankment or trying to stop tree roots lifting pavement, root mats play a role. The term covers both a natural process and a range of manufactured products designed to work with or against root systems.

This article breaks down the different types of root mat products, when each one makes sense, and how to install them properly. We also compare root mats to weed mats and root barriers so you pick the right product for your project.

What Exactly Is a Root Mat

A root mat forms when plant roots spread horizontally through the top 100 to 300mm of soil, creating a dense, interlocking network. This natural matting effect is what holds topsoil in place on slopes, riverbanks, and disturbed ground. Without it, rain washes soil away and wind strips exposed surfaces bare.

In the landscaping and civil construction industry, "root mat" also refers to manufactured matting products, primarily coir matting and jute matting, that encourage this natural root network to establish faster. These products sit on the soil surface, hold seeds and moisture in place, and break down over time as vegetation takes over.

The distinction matters when you are specifying materials for a project. A natural root mat is the end goal. A manufactured root mat product is the tool that gets you there.

• Coir matting: made from coconut fibre, lasts 2 to 5 years depending on weight
• Jute matting: made from plant fibre, biodegrades in 1 to 2 years
• Synthetic erosion mats: UV-stabilised polypropylene, permanent
• Root barriers: HDPE sheeting that redirects roots away from infrastructure

Each serves a different purpose, and picking the wrong one wastes money.

Types of Root Mat Products for Australian Projects

Coir Matting

Coir matting is the workhorse for erosion control and revegetation projects across Australia. Made from woven coconut fibre, it comes in rolls and is available in weights from 400gsm to 900gsm. Heavier weights (700gsm and above) suit steep slopes, drainage channels, and high-rainfall areas.

Lighter 400gsm coir matting works well for flat to moderate slopes where you need seed and soil retention. All Stake Supply stocks coir matting in 400gsm, 700gsm, and 900gsm rolls.

• Biodegradable and adds organic matter to soil as it breaks down
• Holds moisture against the soil surface for seed germination
• Allows seeds to germinate through the open weave
• Performs well in Australian heat and UV conditions

Jute Matting

Jute matting biodegrades faster than coir, typically within 12 to 18 months. This makes it suitable for projects where vegetation will establish quickly, like turf reinforcement or native seed restoration on gentle slopes.

Available in standard 620gsm and thick 750gsm options, including slitted versions that let you plant tube stock directly through the mat.

• More affordable than coir for short-term stabilisation
• Slitted versions allow direct planting without cutting
• Breaks down into the soil, improving organic content

When to Use a Root Mat on Your Project

Root mat products solve specific problems. Choosing the right one depends on your slope angle, how long you need protection, and whether you want to encourage or block root growth. Here is when each type makes sense.

• Slope stabilisation: coir or jute matting on any disturbed slope steeper than 1:3 (18 degrees). Without matting, seed washes downhill before germination.
• Channel and swale lining: heavy coir matting (900gsm) protects drainage channels from scour during peak flows while grass establishes.
• Revegetation after earthworks: any cut, fill, or graded surface needs protection within 14 days under most NSW EPA sediment control requirements.
• Tree root management: if tree roots are threatening paths, pipes, or foundations, a root barrier redirects growth rather than trying to force roots through matting.
• Weed suppression around plantings: jute weed mats placed around individual plants suppress weeds while allowing water through.

How to Install a Root Mat Correctly

Proper installation is the difference between a root mat that works and one that fails within weeks. Here is the process for coir or jute matting on a slope.

1. Prepare the surface. Remove debris, rocks larger than 50mm, and any sharp objects. Grade the surface smooth.
2. Dig an anchor trench. At the top of the slope, dig a trench 200mm deep and 150mm wide. Tuck the top edge of the mat into the trench and backfill.
3. Roll downhill. Unroll the matting down the slope with the grain running downhill. The mat should sit flat against the soil with no air pockets.
4. Overlap joins. Side overlaps of at least 100mm. If joining rolls end to end, overlap by 150mm minimum with the uphill roll on top.
5. Pin the mat. Use biodegradable wooden pegs or metal staples at 1 to 2 per square metre. Pin at overlaps, edges, and anywhere the mat lifts.
6. Seed before or after. Most installers broadcast seed before laying the mat, but you can also hydroseed over the top of jute matting.

• Never drag the mat sideways across a slope. It creates channels for water to run underneath.
• On very steep slopes (steeper than 1:2), double-peg the mat and consider heavier coir.
• Check pins after the first significant rainfall and re-pin any lifted sections.

Root Mat vs Weed Mat vs Root Barrier

These three products get confused constantly. They solve different problems and are not interchangeable. Understanding the difference saves you from buying the wrong product.

The key difference: root mats encourage roots to grow and bind soil together. Weed mats suppress growth on the surface while allowing water through. Root barriers physically block roots from spreading into areas where they will cause damage.

You might use all three on the same project. A root barrier along a path edge, weed mat under garden mulch, and coir matting on the adjacent slope.

Common Root Mat Mistakes to Avoid

Getting the product right is half the battle. Installation errors cause most failures on site. These are the ones we see most often.

• Using the wrong weight. A 400gsm coir mat on a steep, high-rainfall slope will break down before vegetation establishes. Match the weight to the slope angle and expected water flow.
• Skipping the anchor trench. Without a trench at the top, water runs underneath the mat and lifts it off the slope. This is the single most common installation failure.
• Leaving air gaps. The mat must sit directly on the soil surface. Air gaps let water flow underneath, defeating the purpose entirely.
• Not overlapping enough. Less than 100mm overlap on side joins means gaps where soil erodes through. On channels, increase overlaps to 200mm.
• Forgetting to seed. The mat alone is temporary protection. Without seed, you have no long-term root system to hold the soil once the mat biodegrades.

Avoid using synthetic mats where biodegradable ones will do the job. You will end up with plastic waste to remove later, and it adds unnecessary cost to the project.

Choosing the Right Root Mat Weight

Coir matting comes in three standard weights, and each has a specific use case. Picking the right weight upfront saves you from re-doing failed erosion control later, which always costs more than the original install.

• 400gsm: flat to moderate slopes (less than 1:3). Light erosion risk. Seed retention and moisture conservation. Biodegrades in 1 to 2 years.
• 700gsm: moderate to steep slopes (1:3 to 1:2). Medium erosion risk. Suitable for drainage swale lining. Biodegrades in 2 to 3 years.
• 900gsm: steep slopes (steeper than 1:2), channels, and high-flow areas. Heavy erosion risk. Biodegrades in 3 to 5 years.

The investment difference between 400gsm and 900gsm is small compared to the cost of re-doing failed erosion control. If you are unsure, go heavier. All Stake Supply stocks all three weights in 2m x 25m rolls, ready to ship from their St Marys NSW warehouse.

Browse the erosion control range or view the full product range for related materials. For guidance on managing tree roots near infrastructure, the Australian Department of the Environment publishes relevant guidelines, and the Blue Book covers sediment control requirements for construction sites.

Get the Right Root Mat for Your Project

Root mats are a straightforward tool when you match the product to the problem. Coir matting in the right weight handles most erosion control and revegetation jobs. Add root barriers where tree roots threaten infrastructure, and weed mats where you need suppression rather than growth.

Browse the full range at All Stake Supply or contact the team for trade pricing and bulk orders. Family-owned since 1976 with over 1,000 products in stock at their St Marys NSW warehouse, All Stake Supply delivers Australia-wide with a complete delivery guarantee.