What you need to know about topdressing

​Healthy lawns require healthy soil as its base, but it’s not that simple to make changes to the soil once grass has been established…or is it?

​If digging and tilling the lawn is out of the question, you can use a technique known as “topdressing” to add a thin layer of compost, soil, or sand (or a mixture of the three) over your lawn without killing the existing turf — but you’ll need to choose the topdressing material carefully. Typically, your material should match or complement the composition of your existing soil (more details to follow).

Should I topdress my lawn?
Topdressing is a simple way of adding organic material to restore the balance of nutrients in your lawn, creating a better environment for your soil and better overall soil quality. Topdressing can address several common lawn problems:

• Low spots due to rotting tree roots
• Uneven terrain caused by winter freezing and thawing, water runoff, or soil that settled over time
• Compacted soil in areas with high traffic or where water pools
• Bare spots caused by variations in soil texture and nutrients, heat, drought, or other environmental stressors
• Nutrient depletion due to neglect, leaching, or overuse of chemical fertilizers

 
As the organic matter in your topdressing breaks down, it will gradually filter through and improve the soil texture and overall health. More specifically, it can:

• Smooth the surface of the lawn
• Improve drainage and water retention (and be more resistant to drought)
• Keep thatch under control by encouraging decomposition
• Relieve soil compaction problems (especially when combined with aeration)
• Yield a higher rate of germination when applied after overseeding (by protecting the seeds from direct sunlight and retaining more moisture)
• Act as a long-term natural fertilizer (reducing the need for chemical fertilizers)

 
TIP: Topdressing after aerating and overseeding is the ideal trio lawn care techniques that can get you a healthy, lush lawn. Aerating opens up the soil, allowing for better air and water movement. The aeration holes then become the perfect seedbed for overseeding, allowing newer grass to establish and thrive. And finally, topdressing helps to fill in the holes, covering and protecting seed, allowing for better rates of germination and a burst of nutrients as the seedlings establish.
 
What topdressing materials should I use for my lawn?
There’s no one-size-fits-all material that will work with all lawns. The most common, however, is a mixture of sandy loam and organic compost because it helps with proper drainage (the sand helps water seep down into grass roots, and particularly after aerating), good levelling, and nitrogen is produced when the compost breaks down, bringing more nutrients (food) to your soil. The ratio of sandy loam to organic compost will vary depending on the density of the existing soil.
 
Topsoil is one of the cheaper topdressing materials but it doesn’t offer the same benefits as organic compost and sandy loam, so it’s usually only recommended by professionals for levelling out low spots in turf.
 
Generally speaking, the topdressing material should be spread to a depth of ¼ to ½ inch (with the exception of filling in holes, of course). The object is to get as much of the topdressing touching the soil as possible, so the mixture should be fine enough to penetrate the grass surface and reach the existing soil.
 
When is the best time to topdress my lawn?
Early fall or spring are ideal as you’ll allow your grass time to grow through a few mowings before severe heat or cold sets in, which is especially important if you’re planning to overseed your lawn at the same time.

---

Not sure if topdressing is right for your lawn? Think it is and want to get a quote?
​Get in touch and we’d be happy to answer any questions you have.