Topsoil vs Compost : When to use which growing medium (2024)

FAQs

Topsoil vs Compost : When to use which growing medium? ›

Topsoil will provide the volume of soil you need, while compost comes in with its nutrient-boosting properties. According to Gardening Etc. a compost-topsoil mixture is also a good option for potting and container gardening.

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.

Compost – Promotes Healthier Plant Growth. Compost is most well-known for its contribution to healthy and resilient plant growth. It has a number of complementary benefits to plant growth, among them that it balances soil density, adds and retains nutrients, and discourages disease, pests and weeds.

One of the main advantages of topsoil is its ability to improve the quality of existing soil. It can also provide a good base for new plants to grow in. However, topsoil may not contain enough nutrients for plants to thrive, and it may not provide adequate drainage.

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.

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.

There are various ways to use your finished compost. You can sprinkle compost on top or mix it into your flower and vegetable beds, gently rake compost into tree beds, blend it with potting soil to revitalize indoor plants, or spread it on top of the soil on your lawn as a soil amendment.

You can mix compost with topsoil to create your own potting compost, as many of the nurseries do, which gives you the advantages of soil – namely that it dries out more slowly and holds its structure better – together with the benefits of compost – organic matter and more nutrients, a compost made with loam or soil is ...

Growing plants in pure compost can cause problems with water retention and stability as well. When mixed with topsoil, compost works wonders with water, as it allows good drainage through heavy soil while it retains water in sandy soil. Used on its own, however, compost drains quickly and promptly dries out.

Adding too much compost may be harmful, especially in vegetable gardens. You can apply too much compost at one time or over several years. Too much compost in soil stunts plant growth. It also may create water pollution.

When should you use topsoil? ›

It's best to use it wherever you're lacking soil, for example, to fill in a low spot in your lawn, or as a base layer in a new garden that's missing a foundation of soil. If you use topsoil in a garden, you'd still have to add additional compost or manure to help your plants thrive.

Topsoil contains beneficial soil microbes that aid nutrient availability and uptake. But the soil is coarse and heavy, owing to its composted matter, clay, and rock particles. This means that although topsoil is fertile, its properties, like low drainage and aeration, aren't suitable for plant growth.

A general potting mixture of three parts organic matter (such as garden compost, leafmould or well-rotted manure), two parts sharp sand and seven parts topsoil is sufficient for most raised beds. For alpines, bulbs and herbs, that like good drainage, double the proportion of sand.

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.

You can topdress with compost at any time when the ground is not frozen, but if you topdress right after aerating a lawn, you will see even better results. Another great time to topdress with compost is when overseeding a lawn. Applying compost and seeds at the same time will improve germination and moisture retention.

Whereas topsoil is better suited for a wide range of projects, gardening soil usually fits more of a niche need, sometimes even plant-specific needs. Gardening soil is a combination of a mixture of soils and textures that is designed to target a specific type of gardening project.

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.

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.