How much compost do you need?
Determine the appropriate compost application depth for your project. The general rule of thumb is 1/4 to 1/2 inch if applying to the top of the soil and 1 to 2 inches if you plan to amend the soil. Recommended maximums are 30% to 50% compost in a soil blend, but no more than 30% compost in containers or raised beds.
- New lawns — Incorporate 1-2 inches of McGill SoilBuilder Premium Compost to a depth of 4-8 inches into existing soil before seeding or sodding.
- Established lawns — For topdressing and over-seeding, apply a 1/4 to 1/2-inch layer of McGill SoilBuilder or SportsTurf Premium Compost before or after aerating the application site. For patching bare spots or when spreading under established trees and shrubs, apply a 1/4 to 1/2-inch layer and rake in.
- Gardens – Apply 1 to 2 inches of McGill SoilBuilder and incorporate into the existing soil to a depth of 4 to 8 inches.
- Raised beds – Method 1: apply 1-2 inches of McGill SoilBuilder and incorporate to a depth of 6 to 8 inches. Method 2: fill the bed with 6 to 8 inches of McGill LandscapeMix and plant in the mix.
- Trees and shrubs – Dig a hole the same depth as the root ball and two to three times as wide. Based on the width of that hole, and for every 4-6 inches of root ball depth, add 1-2 inches of McGill SoilBuilder or LandscapeMix to the excavated soil and blend. Plant and backfill with the blended soil.
Using the calculator below, (1) select project type, then the shape, (2) enter dimensions OR total planting area, (3) decide if you want the results calculated using square feet or by the acre, (4) enter desired depth, then (5) click the “Calculate” button. The amount of compost needed will appear in the “Results” box.