How Do I Calculate How Much Compost I Need?

by Alex Kountry
Updated on

Calculating how much compost you need is easy with this simple formula. Just follow these steps and you’ll have the perfect amount of compost for your garden in no time!

Checkout this video:


Organic materials such as leaves, grass, and kitchen scraps can be broken down into compost, which is a valuable resource for your garden. Compost enriches the soil, helps retain water, and can reduce the need for chemical fertilizers.

To make the most of your compost, it’s important to know how much you need. This will vary depending on the size and type of garden you have. In this article, we’ll give you some tips on how to calculate the amount of compost you need.

##How Do I Calculate How Much Compost I Need?
The first thing you need to do is measure the area of your garden. To do this, you’ll need to know the length and width of your garden in feet. Once you have these measurements, multiply them together to get the total square footage.

For example, if your garden is 10 feet long and 5 feet wide, the total square footage would be 50 (10 x 5).

Once you know the square footage of your garden, you can calculate how much compost you’ll need using the following formula:

Compost needed (in cubic yards) = Square footage of garden ÷ 100

For our 10×5-foot garden example, we would need 0.5 cubic yards of compost (50 ÷ 100 = 0.5).

Keep in mind that this is just an estimate – you may need more or less compost depending on the type of plants you’re growing and the condition of your soil.

How Much Compost do I Need?

oo much or too little compost can make your plants unhappy. Use our easy compost calculator to work out how much compost you need for your garden. Simply enter the length and width of the area you want to cover and our compost calculator will do the rest!

Estimating the Volume of Compost Needed

When it comes to how much compost you will need for your garden, there are a few schools of thought. The first rule of thumb is one cubic yard for every 1,000 square feet (93 m2) of garden area. This works out to be about 3 inches (7.6 cm) deep if you are applying it to the entire garden area. If you are just using it as a top dressing or planting in beds, you will need less.

Another rule of thumb is 1 pound (0.45 kg) for every square foot (0.093 m2). This works out to be a layer about 1/4 inch (0.64 cm) deep over the entire garden area.

A third way to estimate the amount of compost you need is by measuring the length and width of the area you want to cover and multiplying those numbers together. Once you have that number, multiply it by the depth in inches that you want your compost to be. This will give you the total number of cubic inches (or cm3) of compost you need. To convert cubic inches to gallons, divide by 231 (the number of cubic inches in a gallon). To convert cubic centimeters to liters, divide by 1,000 (the number of cubic centimeters in a liter).

Calculating the Weight of Compost Needed

To calculate the amount of compost you need, start by estimating the total weight of waste you think your project will generate. Most compostable materials fall somewhere in the 25-75% moisture content range. You can use this calculator to determine the approximate weight of your wet or dry materials.

Next, convert your estimate of total weight into gallons using this conversion rate:

1 gallon = 8.34 lb

For example, if you have 1,000 lb of waste, that would be approximately 120 gallons (1,000 lb ÷ 8.34 lb). Once you have an estimate of the amount of waste in gallons, use the following equation to calculate how many pounds of compost you will need:


In general, a compost pile should be at least 3’x3’x3′, but adding more material will help the compost process to happen more quickly.To calculate how much compost you’ll need to add to your garden, start by measuring the area you want to cover. Then, using a ruler or tape measure, calculate how deep you want the compost to be. Finally, multiply those two numbers together to find the total volume of compost you’ll need.For example, if you want to cover an area that is 10 feet long and 5 feet wide with a 2-inch layer of compost, you would need 20 cubic feet of compost.

Photo of author

About the author

Alex Kountry

Alex Kountry is the founder of HayFarmGuy and has been a backyard farmer for over 10 years. Since then he has decided to write helpful articles that will help you become a better backyard farmer and know what to do. He also loves to play tennis and read books


HayFarmGuy - Get Info About Farm Animals in Your Inbox

Leave a Comment