How do I topdress my lawn with compost?
Creating a beautiful lawn all starts with a healthy soil. Since adding compost is the best way to improve your soil’s health, sprinkling some compost over your grass is a great way to give your lawn the nutrients and organic matter that it needs to be beautiful.
You can topdress a lawn with compost in the spring and fall, and it’s even more powerful when you do combine it with aerating and/or overseeding your grass. Since grass in the greater-Manassas, VA area sometimes goes dormant with the summer heat and the ground is frozen in the winter, adding compost in the spring or fall is best.
Step 1: How much compost do I need?
You want to use ¼’’ to ½’’ of compost when topdressing your lawn. This gives you enough compost to provide benefit to the soil beneath while still ensuring that your grass blades will stick up through the compost so that they get sunlight.
If you are aerating your lawn and/or cutting your grass relatively high, it’s best to use closer to a half inch. If you’re going to overseed your grass, stay close to a quarter inch of compost so that the compost doesn’t smother the grass seeds.
For every 25 square feet of lawn that you have, you will need about one-half of a cubic yard if you are going one-quarter inch deep, or one cubic foot if you’re planning to lay the compost one-half inch thick.
For smaller lawns, you can probably buy bagged compost. One cubic foot is a popular amount to put into a bag so that it isn’t too heavy, but there are some compost bags that are 1.5 cubic yards in the greater-DC area. If you need more than 10 bags, it will likely be more cost effective to buy bulk compost near you.
Step 2: Buy a good compost
We’ve created a buying guide to help you choose a quality compost. You want it to be free of trash, rocks, and other debris, as well as made from materials that you are comfortable with. Lastly, since you don’t want to be introducing weeds into your grass, it’s best to choose a compost that was made using a relatively high heat (above 140 degrees). This means that you may want to save your home compost pile for elsewhere in your garden and buy compost that is made at an industrial or municipal composting facility.
Step 3: Mow your lawn
You typically want to mow your grass to 1.5-2 inches when applying compost with most of the grasses in our area, like Fescues and Bluegrass. This will make spreading the compost easier as well as aerating and overseeding (if you’re taking these steps).
Step 4: Place the compost around your yard
Put small piles of compost around your yard. Drop the bagged compost every few feet or tip a wheelbarrow with the loose, bulk compost. The compost piles should be evenly spaced with just a few shovels each. Placing many, small piles will help you rake out the compost (during the next step), so it might be helpful for large lawns to try a few piles and then rake them out (step 5) so that you can make sure your spacing is right.
If you are aerating or overseeding your lawn, you should do these steps before placing down the compost.
Step 5: Rake the compost across the grass
Spread the compost over your lawn. There are a variety of ways to do this—I like using a metal rake or, for really large lawns, pulling part of a chain link fence behind me. You should spread the compost in all directions so that there is complete coverage across your full lawn, and the compost layer should be thin enough so that most of the grass blade is visible through the top of the compost.
Step 6: Water your lawn
Adding water after you’ve spread compost helps the material to start working its way down into your soil and, importantly, helps wash the compost off of any grass blades so that they have access to sunlight. You can also topdress your lawn before a light rain so that you don’t have to do this step yourself, but you don’t want too much water (from nature or your watering system) over the first few days so that the compost stays in place.
That’s it! With six simple steps, you’re well on your way to healthier soil and a better looking lawn.
We make premium and local compost, mulch, and topsoil in Manassas, VA. They are specially designed to increase the health and productivity of our local soils, and with our focus on sustainable practices, this lets the environment and your garden grow good, together. We sell bulk and bagged compost, bulk natural mulches, bulk and bagged dyed mulches, and bulk topsoil.