Frequently Asked Questions
Compost can be used for topdressing a lawn, but it is not the best material for topdressing. Compost typically contains larger pieces of wood or other organic debris that is difficult to work down through the soil canopy. Adding more organic matter to a turf that has excessive thatch may contribute to the spongy, soft surface. Topdressing sand is the preferred material for topdressing lawns (based on decades of research by the USGA). It provides aeration, levelling, and long-term soil benefits. However, River Sand blends compost to create a Topdressing Blend if preferred by a client, and benefits from compost are still achieved.
You can add a little topsoil to the surface of an established grass or turf to help repair or level an area. This is not the same process as topdressing though. Make sure to rake the topsoil in the best you can and only apply a thin layer at a time so that the grass still shows through and can gather sunlight to recover quickly. This method is best for small areas to repair such as a tree removal, dog paths or digging, and other turf holes.
Topdressing is a great way to level a lawn. Applying a thin layer of sand or soil can help level the lawn. Be sure not to apply too much depth at one time if applying on top of an established turf grass. Use the back of a rake or a broom to smooth out the material in small areas. For large topdressed areas, use a drag or a type of smoothing device (old fence, heavy board, etc.) to smooth out the topdressing sand.
You can use the same sand for both but they are not the same. Topdressing sand is designed more for the purpose of topdressing turf and the gradation is composed of medium sized particles. The same sand is not optimal for bunkers as it can become unstable and lead to fried egg lies or buried balls (low penetrometer readings). However, your bunker sand should not contain particles that if hit onto the green cause damage (large particles). Bunker sand is designed with more uniform gradation and angular particle shapes.
Yes, in most cases core aerating along with top dressing is very beneficial. The cores are a better option than just spike aerating as it allows the topdressing material to penetrate into the rootzone. Core aerating also removes thatch layers and compacted soil plugs. The cores can be left and allowed to break back up as you drag the topdressing into place and level the surface.
Topdressing a lawn can improve your turf health and appeal. Topdressing Sand is still the best material to level and topdress your lawn. Compost has become a popular alternative because it is easy to apply and can cover a lot of area per ton. However, most professional golf courses and sports fields still topdress with sand alone. The method is backed with decades of turfgrass research. Sand spreads and levels a surface easily. Sand also increases porosity immediately within the rootzone to promote deep roots with good water and air infiltration. Compost adds organic matter to the soil along with beneficial microbes. However, a healthy turf may not need more organic matter as it produces its own (thatch) and it should already have an established microbial ecosystem. The more practical side of compost application is that you end up with the larger pieces of debris (wood, peanut hulls, leaves, etc.) left on top and a portion of it blown off with the next mowing. The issue with applying a good topsoil is that it is more difficult to spread and it may contain small rocks/pebbles that are not good for any mowers, especially reel mowers. RSI still offers all types of sand topdressing, sand/compost topdressing blends, loamy soil topdressing, green topdressing, and sand/peat blends for topdressing. If you have a preference let us know.
Topdressing is not a new practice for golf courses and athletic field turf. Lawn turf is often a similar turf, usually bermuda or zoysia. Sand has been the standard topdressing material for decades and it backed by decades of research and application by the leading turfgrass professionals. Sand spreads evenly over the turf to provide a level surface for an even cut by the mower, preventing scalping. Sand is also an inert material, meaning that it will stay within the soil creating pore space for infiltration of air and water. Sand along with core aerating reduces compaction of high clay content soils. Sand also helps alleviate excessive thatch build up. A heathy turf already has beneficial microbes within the soil, but excessive thatch or shallow roots can lead to the loss of turfgrass health. RSI has a variety of topdressing sands for different applications and turf types. Our topdressing may be dyed green or blended with compost if preferred.
If your turf has brown areas from unlevel spots after mowing (scalping), then topdressing can help level the soil surface and promote healthy turf. Also, if you take a plug and see excessive thatch build up or shallow roots, topdressing along with core aeration will help promote healthy turf. The time of year to apply topdressing sand is key. Warm season turfgrass such as bermuda, zoysia, and centipede should be topdressed once it has begun to turn green or is green. In Georgia, that is typically when soil temperatures reach optimal level in April or May at the earliest. Topdressing season can extend through June and July into August. The limiting factor is allowing enough time for it to grow through the topdressing application before it goes dormant. Topdressing cool season grasses such as fescue and rye is best done with overseeding in the Fall.