Topsoil, Mulch, & Compost: What’s the Difference and How to Use Them (2024)

Topsoil, Mulch, & Compost: What’s the Difference and How to Use Them (1)

When landscaping your yard or setting up a new garden, it’s important to know how to use certain organic materials to get the most out of your plants. Three of the most commonly used materials are mulch, compost, and topsoil.

Understanding the difference between this soil trio is essential, but even more important is knowing which to use, where, and when.

How to Use Topsoil and Compost

Topsoil is the upper, outermost layer of soil that is usually composed of the top few inches. It has the highest concentration of organic matter and microorganisms and is where most of the Earth’s biological soil activity occurs. Plants generally concentrate their roots in this layer and obtain most of their nutrients here.

The Need for Topsoil

In the days of our grandparents, the topsoil was naturally very thick and deep but due to land clearing, over-farming, and other unsustainable agriculture practices, our soil has been depleted. So much so, that in many places across the country, there is little to no topsoil left at all.

If you are preparing a site for planting edibles or ornamentals, it’s important to start with good soil that is high in nutrients and will feed your plants as they grow.

The easy way to accomplish this is to simply buy prepared topsoil, then add it to your site before planting, mix it into the existing soil, and begin planting. If you have time, however, you can create topsoil by yourself. Toss organic matter like grass clippings, discarded fruit, leaves, etc. into a pile where it receives air and water it will naturally break down, resulting in compost. Mix the compost into the top layer of your planting area and you are good to go.

Difference Between Topsoil and Compost

Compost and topsoil are essentially the product of decomposed organic matter. They are both high in nutrients and beneficial organisms. They are both an excellent addition to your garden, but are they the same? Not really.

While they share many of the same attributes, compost and topsoil differ in their application. Compost is often only used as an organic amendment, the result of letting organic materials breakdown until they are a fine texture.

Compost is usually used more as potting soil, a top-layer fertilizer to your plants, or to amend your current soil. Whereas topsoil is better for building up your soil level or as a landscape filler. In fact, many times when you order topsoil in bulk, what you get is dirt with some organic matter blended in.

As a result of the collection, reduction, and recycling of tree and land clearing debris, Gaston Mulch and Soil produces topsoil as the biomass material decomposed and screened, creating topsoil that is the best of both worlds.

How to Use Mulch

After you’ve created a base layer of topsoil, then enriched it with compost, you need a cover to keep it cool and moist, and prevent weeds from competing with the more desirable plants in your garden.

This is where mulch comes in. In addition to beautifying your landscape, mulch helps prolong the life of your plants and keep your soil intact. Over time, mulch will break down and effectively become topsoil but it shouldn’t be used in lieu of topsoil. That said, while you could leave your topsoil uncovered, it is wise to cover it with mulch to avoid erosion from the rain and overheating from our hot sun.

Gaston Mulch, Topsoil, and Compost

While you may not have considered all the differences between these different soil amendments, it’s important to use them properly.

To reiterate: Lay a base level of topsoil, enriched with compost, and cover it with mulch.

At Gaston Mulch and Soil, we create our compost, topsoil, and mulches from the highest quality, recycled tree debris. If you are starting a garden, or refreshing your landscape, contact us. We’d love to help with your project.

Topsoil, Mulch, & Compost: What’s the Difference and How to Use Them (2024)

FAQs

Topsoil, Mulch, & Compost: What’s the Difference and How to Use Them? ›

Compost is usually used more as potting soil, a top-layer fertilizer to your plants, or to amend your current soil. Whereas topsoil is better for building up your soil level or as a landscape filler. In fact, many times when you order topsoil in bulk, what you get is dirt with some organic matter blended in.

When to use topsoil vs compost? ›

Compost is also much richer in nutrients than topsoil, making it an ideal supplement for soil that is lacking in nutrients. Another difference between compost and topsoil is their use. Compost is most commonly used as a soil amendment, which means it is added to existing soil to improve its fertility and structure.

Should I use mulch or topsoil? ›

Adding topsoil alone does not ensure soil performance, especially if the “topsoil” is mostly inert and contains little to no organic matter or active soil microbes. Mulch is a material applied to the soil surface to discourage weeds, provide shade and reduce moisture loss through evaporation.

Do you put compost on top of the soil or mix it in? ›

Add compost to soil before you install landscape plants. Spread a 3- to 4-inch layer of compost over the area you intend to plant. Mix the compost into the soil as deeply as possible. Then install new plants into the amended soil.

Should I use compost or mulch? ›

The layer of leaf litter or compost will provide extra nutrients and break down more quickly than the mulch. Add a maximum of 2–3 inches of mulch to your garden. A deeper layer could deprive the soil of oxygen and block moisture. Never pile up mulch at the base of a plant; it will encourage rot and infection.

Does grass grow better in compost or topsoil? ›

If you're trying to grow a thick, lush carpet of grass, both topsoil and compost can be effective. Either one can be used to address bald spots in your lawn, by adding two to three inches' worth of topsoil or compost to the area and incorporating it into the existing soil to encourage grass growth over time.

Do you put plants in soil or compost? ›

Compost can dry out quite quickly, so mixing it with topsoil is a great way to provide balanced bedding for plants and flowers. You get the best of both worlds with a mixture since topsoil will offer a robust home for roots with plenty of water, while compost will provide a boost of nutrients.

Can I put topsoil over old mulch? ›

Your old mulch should be breaking down but you can certainly top it with new. That said, your plants should be filling in so that you don't need to use mulch at all. I only use mulch when I start a new bed or temporarily if I remove something large.

What plants don't like mulch? ›

There are some species that tolerate excessive mulch better than others. Some of the worst effected plants are grassy plants (iris, daylilies, liriope, etc.), Indian Hawthorn, Azaleas and Loropetalum.

What is the best mix of compost and topsoil? ›

This will help loosen the subsoil which will improve drainage and aeration. (Do not lift and flip the soil over.) Add a mixture of compost and purchased topsoil in a 1:2 or 1:1 ratio, to the top of the bed. There are vendors who sell topsoil mixed with compost.

Can you plant straight into compost? ›

Compost is one of the best garden amendments available. You can plant in straight compost, but I suggest incorporating it into your sandy garden soil or mixing it with other additives if you want to use it for container plantings.

Can you compost straight into the soil? ›

The method of direct compost is very simple: It's a matter of taking food scraps to the garden, digging a hole, filling it with the food waste, and covering it back up.

Can compost be left on top of soil? ›

You can add compost to your flower and vegetable beds, window boxes, and container gardens; incorporate it into tree beds; mix it with potting soil for indoor plants; or spread it on top of the soil in your yard. Compost can be used as a soil amendment or as a mulch.

When should you not use compost? ›

Dairy and other animal products

While animal products (meat, fish, eggs, bones, dairy, grease, fat) are organic, they can create odor problems and attract flies, rodents, and other pests to your pile or bin. These products can also carry pathogens that may survive the home composting process.

Can I mix mulch with compost? ›

Spread compost directly over the cardboard and then cover it with bulky materials like wood chips to optimize water conservation and weed control. This layer should include about 1.5 inches of compost covered by 3 inches of mulch. The top layer of mulch mimics the newly fallen organic matter of a forest.

Do you need fertilizer if you use compost? ›

Compost and fertilizer are complementary, and both play an essential role in keeping your crops and the soil healthy.

Should I top dress my lawn with compost or topsoil? ›

How to Add Top Dressing to My Lawn. In the spring, apply 0.25–0.5 inches of top dressing after mowing your lawn low with compost, sand or topsoil. The best choice depends on your current soil and issues. Compost is a great all around option for both helping with drainage and providing organic material.

Can I use compost in place of topsoil? ›

The rule for topsoil is that for general projects, it is the perfect option to get your plant's growing well. Now compost works really well, but for slightly different projects. If you are planting into pots then the plants will need extra nutrients because they are in a confined space.

When should I put down topsoil? ›

You can apply topsoil anytime, but most gardeners like to add it in spring before planting. In the fall, it may also be added as a top dressing that will allow nutrients to break down into the soil.

References

Top Articles
Latest Posts
Article information

Author: Corie Satterfield

Last Updated:

Views: 6378

Rating: 4.1 / 5 (62 voted)

Reviews: 85% of readers found this page helpful

Author information

Name: Corie Satterfield

Birthday: 1992-08-19

Address: 850 Benjamin Bridge, Dickinsonchester, CO 68572-0542

Phone: +26813599986666

Job: Sales Manager

Hobby: Table tennis, Soapmaking, Flower arranging, amateur radio, Rock climbing, scrapbook, Horseback riding

Introduction: My name is Corie Satterfield, I am a fancy, perfect, spotless, quaint, fantastic, funny, lucky person who loves writing and wants to share my knowledge and understanding with you.