ABC Blog

Can You Use Compost as Soil?

a shovel in compost

Compost, often called “black gold,” adds rich nutrients to your soil that help your garden thrive. However, is it possible to use compost as soil and leave out the soil altogether?

While using compost as soil works in some rare instances, it is not recommended. This quick guide will explain why you shouldn’t use compost as soil and the important differences between compost and potting soil. It will also go over how to use compost correctly with your soil to benefit your garden the most.

Can You Use Compost as Soil? 

Compost is a nutrient-rich material that offers many benefits for your garden. However, should you use compost as soil? While compost and soil may seem interchangeable, they are two separate materials that should be used differently for the best results in your garden.

It is sometimes okay to use compost as soil, but those instances are rare. For example, you can use compost as your growing soil with some low-spreading plants that thrive in acidic conditions. Some acidic-loving plants include squash, broccoli, cucumber and pumpkins.

However, for a compost-only method to work, the compost must be mature so that the bacteria are less active. Mature compost is dark brown, has a crumbly texture and has an earthy smell.

Most of the time, it does not work to use compost as soil. Each material serves its own purpose in the garden; using them together is better.

There are several key differences between compost and soil that homeowners should keep in mind. First, potting soil is specifically formulated to help plants thrive and grow in pots. It is usually a combination of peat moss, perlite, vermiculite and other organic matter. It’s designed to drain water efficiently, retain needed moisture and give your plants the nutrients they need to grow.

Compost, on the other hand, is made from decomposed organic matter. Kitchen scraps, plant debris and yard waste make excellent composting materials. Compost is high in nutrients.

Compost can improve soil structure and help plants grow when paired with potting soil. However, with most plants, compost does not have the proper aeration or drainage needed to be used by itself.

How to Use Compost

High-quality compost is the perfect complement to potting soil. You can incorporate compost into your potting soil in several ways to enhance your plants’ soil structure and health.

First, you can mix compost into your potting soil before you plant. How much compost you need depends on each plant, so read the directions or as a lawn service specialist before planting. This method works well with potted plants and for raised bed gardens.

You can also sprinkle compost as a slow-release natural fertilizer on top of your soil. Simply sprinkle the compost at the base of your plant and gently mix it into the topsoil. Your plants will love the balance supply of nutrients it provides them.

Compost can also be used as mulch. Applying a layer of compost around your plants can suppress weed growth while helping to retain moisture and prevent soil erosion. Plus, it will slowly release nutrients into your plants.

Some gardeners like making their own compost tea to nourish their gardens. You steep your compost in water and store the “tea” in a container. You can water your garden or spray it directly on your plants’ leaves for extra nutrients.

Contact a lawn service specialist if you need help using compost in your garden. They can answer your questions and apply the compost for you for the best results.

a blue shovel of compost

How Long Does Compost Take?

Making your own compost is a rewarding activity that provides endless benefits to your garden. Plus, it puts your kitchen and yard scraps to good use instead of sending them to landfills. Homeowners who are new to composting frequently ask how long compost takes to make before they can use it in their gardens.

The time required to make compost can vary depending on several factors, including the composting method, materials used and environmental conditions. In general, compost takes several months to a year to reach its full maturity.

The size of the compost pile and how often you turn it also impact the time it takes for the organic matter to break down. While some materials can fully break down in only two weeks, that does not mean that your compost is ready to use.

How To Tell Compost Is Ready

Using compost at the right time is crucial to benefit your plants most. Several signs indicate that your compost is mature enough to use in your garden.

First, mature compost is extremely dark brown, which is how compost got the label “black gold.” The texture should be crumbly and resemble rich soil. You should not be able to recognize any of the organic matter because it has all broken down into a soil-like texture.

Next, mature compost has an earthy smell. It should not smell foul or unpleasant. If it does, it’s likely due to a chemical off-balance in your compost. You may need to add more green or brown matter to correct the problem.

The internal temperature of your compost should feel cool before you use it. The best way to test the temperature is to stick your hand into the middle of the pile and see how it feels. The materials have not fully broken down if it is still warm.

Finally, finished compost will not give off any steam or vapor. Because of microbial activity, it’s normal to see steam and vapor when the organic matter is still breaking down. Once it stops giving off steam, your compost may be mature enough to use in your garden.

a compost bin

What Food Scraps Can Be Composted?

Another question that homeowners new to composting ask is what food scraps can be composted and which should be avoided. Luckily, there is a huge array of food types that can be composted, such as:

  • Fruits and vegetables
  • Crushed eggshells
  • Coffee grounds
  • Tea leaves
  • Nuts and nutshells
  • Bread
  • Pasta
  • Non-greasy paper

Some organic materials are more beneficial to compost than others. For example, fruit and vegetable scraps, such as peels, cores and other trimmings, add vital nutrients to your compost pile.

Used coffee grounds and tea leaves add nitrogen to your compost pile, which helps improve the texture of your compost. Rinsed and crushed eggshells are high in calcium, benefiting your plants.

Nuts and their shells add carbon to your compost pile, which helps balance the nutrient levels.

You technically can compost some items; however, you should be mindful of how much you add to your pile. For instance, stale bread and pasta can attract pests, so they should be added in moderation.

Paper products such as used napkins, unwaxed paper towels and parchment paper can be composted, but paper with a lot of grease or oil should not be added to your pile.

There are also some foods and organic materials you should avoid adding to your compost altogether, such as:

  • Meat and fish
  • Dairy products
  • Processed foods
  • Too many citrus peels
  • Diseased plants

These items can attract pests to your pile, slow down the composting process, throw off the chemical balance and add unwanted and unnatural additives to your compost.

Enjoy a Thriving Garden Today

Planting with compost delivers much-needed nutrients to help your plants thrive. However, it should not be used as soil. For best results, use compost as an accompaniment to your soil.

The amount of time it takes to make compost varies on several factors, such as the size of the pile and environmental conditions. The types of organic matter you add to your compost also make a difference.

If you want your yard to enjoy the benefits of compost, contact a lawn service specialist for help. They will set you on the right track for your garden to thrive.

ABC Can Create the Best Lawn Service Schedule for Your Yard

There are so many things to consider when creating a lawn service schedule. Instead of playing a guessing game, contact ABC Home & Commercial Services. Our lawn service professionals will keep your lawn healthy and green with compost made here in Austin—Dillodirt.

J Zambo

J Zambo joined ABC in 2023 with over 20 years of experience. He is the Lawn & Tree Division Manager, overseeing Lawn Maintenance and Care, Landscaping, Tree and Holiday Lighting for all ABC Austin branches. Before ABC, he was the Vice President of Aloha Arbor Care and Hawaii Landscape Services. J is an ISA Certified Arborist and ISA Qualified Tree Risk Assessor. His favorite quote is “So shines a good deed in a weary world” by Willie Wonka.

Learn More

Comments are closed.