Scotts Lawn Builder Topdress Mix and Underlay Organic Lawn Soil

Scotts Lawn Builder Topdress Mix and Underlay Organic Lawn Soil

Size: 25L

Main product features

Feeds for up to 3 months
Feeds for up to 3 months
Thicker lawn
Thicker lawn
Waterlock technology
Waterlock technology

Lawn Builder Topdress Mix and Underlay Soil rejuvenates, feeds and improves soils to encourage better looking, healthier lawns. It's an organic lawn soil with added Scotts Lawn Builder™ slow-release fertiliser designed to make lawn care easy.

When to use



  • Contains composted organic materials as well as a slow-release fertiliser. Does not contain any animal waste or by-products
  • Includes a quick-release iron that helps green lawns up rapidly
  • Slow-release of nutrients eliminates waste through run-off and leaching and prevents burning
  • Wetting agent assists moisture to soak into the soil and improves nutrient uptake through roots
  • Traditional lawn foods release or 'dump' most of their nutrients within a couple of weeks of application, causing a rapid surge in growth that quickly drops off again as the food supply diminishes. Scotts Lawn Builder™ uses patented time-release technology to ensure nutrients are released slowly and continuously over a three month period
  • Lawn Topdress Mix complies with the requirements of the appropriate standard for a composted soil conditioner



  • All lawn grasses including all named varieties of buffalo, traditional couch, Santa Ana couch, kikuyu, bent, fescues and carpet grass
  • All grass substitutes such as dichondra (also known as pennywort or kidney weed), lippia, zoysia
  • Topdressing existing lawns and mixing into existing soil when preparing areas for sowing lawn seed or laying instant turf



  • Scotts Lawn Builder™ Topdress is not recommended for use on garden beds
  • Do not use on lawns less than 8 weeks old - from germination of seed or installation of instant turf


  • Lawn Topdress Mix adds organic matter to impoverished soils to improve soil texture, moisture-holding and overall soil health
  • When applied as a topdressing, it can be used to remove hollows that may have developed
  • Provides a healthy soil environment for sowing lawn patching and repair products
  • Its nutrients are released at about the same rate that grass roots can take up the fertiliser so there is no wastage, run-off to waterways or damaging surge growth



  1. Lawn Topdress Mix may be spread thinly over an existing lawn alone or in combination with over-seeding to boost lawn density
  2. Spread evenly over the grass and rake to level the area. If over-seeding, use quality seed and follow package directions
  3. For lawns that have a build-up of dead grass under the green top growth ("thatch"), raking with a steel tine garden rake followed by aeration with a sturdy fork is recommended before topdressing
  4. To prepare an area for a new seeded or turfed lawn, spray the area with a non-selective herbicide such as Roundup according to label directions at least 10 days before planting, to eradicate all existing weeds and grasses
  5. Dig out dead weeds and grass then loosen the soil. Spread a 2.5cm layer of Lawn Topdress Mix and mix into top 2.5cm of the existing soil
  6. Spread seed or lay turf and water frequently. After 8-10 weeks, feed with Scotts Lawn Builder™ All Purpose Slow Release Lawn Food

For a complete guide on how to use Scotts Lawn Builder™ Topdress Mix, watch the video on this page and always check the packaging



  • Topdressing an existing lawn is best done in Autumn, after the heat of Summer has passed and before Winter rainfall
  • It can be done at other times of the year but avoid topdressing in mid Summer
  • Sowing new lawns and patching existing grass are best done in mid Spring, allowing time for the seeds to germinate and grass to establish before Summer
  • New turf is best laid in Spring or Autumn - avoid Summer's heat and Winter's cold



IMPORTANT: We recommend using gardening gloves when using this and other planting mixes and composts

Store safely out of the reach of children and pets. This product contains iron which can be harmful to dogs' livers if eaten in quantity

SAFETY FIRST: Read the instructions on the product packaging before use and take particular note of any warnings or cautions on the label 

See the Safety Data Sheet for this product



Health and Safety

Always read the pack label and product instructions carefully before use. For further information relating to product safety please review the product data safety sheet link below.

Scotts Lawn Builder™ Topdress Mix and Underlay Organic Lawn Soil main image
Scotts Lawn Builder Topdress Mix and Underlay Organic Lawn Soil 25L (other sizes available)
Related articles

Find your local store

Searching for expert advice? Or just looking for the perfect product? Visit your local store and get help from dedicated staff.