Turf Underlay

Why Put Soil Under Your Turf?

When laying new turf you only get one chance to get it right, because once it is laid there is no going back. Turf underlay soil is the foundation (also know as the bed) for your turf to grow on. Laying new turf on recommended soil gives your new lawn encouragement to develop new roots and thrive.

With turf underlay you are aiming to promote a healthy root system for your turf to establish and then continue to grow, protecting if from various weather conditions such as drought and winter frost. The underlay should be a firm base that allow downward movement of water as well as water retention.

What Makes Good Turf Underlay?

Turf underlay is critical to your newly installed lawn. It gives your lawn the nutrients it needs to establish and grow healthy. An ideal underlay is a sandy loam, with approximately 20-30% soil and 70-80% sand. The component of sand creates a good, long-term profile allowing free-flowing water movement, whilst the soil helps hold moisture. To give your lawn the best chance of strong root development, the mix consist of a balance of carefully sourced nutrients and minerals.

Where Can I Buy Turf Underlay?

Greener Lawn is now supplying our customers with quality underlay soil. Simply give us a call with how much soil you need and we will provide you with a quote and the delivery options available. If you don’t know how to calculate the soil needed, checkout the formula below or our friendly office staff will be more than happy to help.

How Much Turf Underlay Do I Require?

When calculating how much turf underlay you require, you should work off a minimum of at least 75mm of soil.

How does this work when it comes to excavations and laying your new turf? The excavated level should be at least 100 mm below pathways, driveways and garden edging. This allows you to apply at least 75 mm of turf underlay and leaves the remaining space to lay turf which makes it level to your pathways, driveways, and garden edging. If the excavated area allows you to add more than 75 mm of soil, that’s okay just add more turf underlay until it is 25-40mm (depending on your personal preference) lower than the path.

Before spreading your turf underlay, loosen up the existing soil and apply gypsum if it’s a clay based soil.

To calculate how much underlay you need to order, you will need to know the area of where you plan to lay your turf and the depth of underlay you desire. Simply multiply those numbers to find the m3 you require and add 25% to convert the measurement to tonnes.


Measure two sides; side A and B. Then multiply them together      Example: area is 8m x 8m with a desired depth of 75 mmA x B = Area  8 x 8 = 64m2

Area x depth = M364m2 x 0.075 = 4.8m3

Add 25% to convert m3 to tonnes4.8m3 + 25% = 6 tonnes