Top dressing a lawn may be seen by some as a step too far. “Surely”, you may be thinking to yourself, “the fact that I water it is enough.” And you may well be right. If your soil is healthy, level, and well fertilised, you may not require top dressing. If one or more of those boxes are un-ticked, however, your lawn may benefit from a top dressing in a BIG way.
What is Top Dressing?
Top dressing is the process of spreading a specifically made soil mixture over your lawn, up to a depth of 1cm. This layer of mixture has a variety of uses, from correcting poor soil preparation prior to seeding by filling in low spots and evening out the lawn, to adding nutrients that may otherwise be missing from the soil.
Top dressing your lawn can help your lawn in a few different respects. On top of leveling and enriching your soil, it also helps prevent the build-up of the dead grass blades and stems know as thatch, improves both the drainage and nutrient retention of your soil, and increases its resistance to pests and diseases.
How Do I Go About Top Dressing?
It all depends on what your main motive for top dressing is.
If it’s as simple as adding nutrients to your existing soil, and there’s no need to even out any high or low points in the lawn, then spreading couldn’t be easier!
- The first step is to mow your lawn back to as a low a height as is recommended for the variety. Remember – different types of grass can be mowed to different heights, but they all use the 1/3 rule: Never take more than 1/3 of the blade height off at once
- Ensure your mower has a catcher, as you want to have as few barriers between the top dressing and the soil as possible. This also means you need to rake up any excess organic matter after mowing.
- Spread the mix evenly over the area. Depending on the size of the area, you could do this with a professional spreader (available for rent at any good nursery), a shovel, or by hand.
- Once you’ve laid the top dressing, rake it until it is as evenly dispersed as possible. You want it no deeper than 1cm, and need to ensure that, at the very least, the tips of the grass blades are showing.
- Water in the top dressing and you’re done!
For those who are top dressing in order to level out their lawn, it’s the same general process with the addition of a couple of steps:
- After you mow the lawn, fill in any dips as best you can with either existing soil from your property, or a clean sand. Use a straight edge to help you get the turf as level as possible.
- Once it’s reasonably level, water in the sand or soil to allow it to properly fall into the lawn’s gaps.
- Once it dries out a bit, apply the top dressing as above.
If the lawn indentations are dramatic – i.e. more than 5cm deep – you may find that the existing lawn will die off if you fill in the hole with soil or sand. In this case, it’s best to dig up that entire patch of soil, fill in the hole, and re-seed or re-sod the area from scratch.
When Is the Best Time to Do It?
The best time of year to top dress lawn is in their peak growing season. Depending on whether you have a warm season or cool season grass, this could be anywhere between early spring and late autumn. You’ll know it as the time that you most often have to mow.
Top dressing at this time of the year will allow the lawn to quickly grow through the new layer, re-establishing itself sooner rather than later.
It’s as simple as that! If you have any queries on top dressing your lawn, don’t hesitate to contact a McKays’ seed specialist.