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Compost vs. Mulch: How and When to use Compost and Mulch

Vibrant, thriving gardens are not simply born; they’re made with love, care, and lots of gardening expertise. 

If you’re a professional or even an amateur gardener who is trying to cultivate a beautiful garden, you’ll know that the process involves a lot more than simply selecting and planting plants. 

It involves a deep knowledge of knowing what they need to grow and stay healthy and how to use gardening tools and fertilizers such as compost and mulch. 

To the inexperienced, the terms’ compost’ and ‘mulch’ are often used interchangeably. 

However, each has its own unique composition and purpose, and – when used correctly – each can play an important role in your garden’s health and vitality. 

This guide explores how to use compost and mulch, the differences between the two, and when you need to use them. 

What are Compost and Mulch? 

At first glance, compost and mulch are pretty similar. 

They are both spread across or mixed in soil, and both work in their own ways to keep plants healthy. 

However, that’s where the similarities end. 

Compost is made with organic materials like leaves, fruit and vegetable peels, cotton cloth scraps, and other natural waste. 

Mulch, meanwhile, can be both organic and inorganic; mulch can be made with organic material like wood chips, leaves, grass, and straw but can also be made with inorganic material like gravel, stones, or plastic. 

As well as being different in their compositions, mulch and compost are also different in how and why they’re used. 

Mulch is spread over the soil to keep the soil and budding plants cool, to stop weeds from growing, and to protect the soil from the sun so that it doesn’t lose moisture. 

Mulch reduces the amount of physical maintenance that the soil needs. Over time, organic mulch can break down and seep into the soil, acting as a fertilizer.

Meanwhile, compost’s primary purpose is fertilization; it’s mixed with soil as a ‘soil conditioner’ to improve the quality of the soil and help plants grow in it. It’s so beneficial to plants that some gardeners call compost black gold!

How and When to Use Mulch 

Once you’ve understood what mulch is and why it’s important, try to gain a better understanding of how and when to use it. 

In most cases, mulch should be applied once a year, either in mid-spring and mid-fall. However, use your gardener’s sense; if the already existing layer of mulch looks like it’s broken down and been absorbed into the soil, then it’s time for a new layer. 

You also shouldn’t wait a year if you notice weeds growing through the soil. 

When you’re using mulch, there are several steps to consider. 

Choosing the mulch 

Choose your mulch based on where you plan to use it. Biodegradable mulch, which can be made with leaves, wood chips, and grass clippings, can be helpful when you want to improve your soil quality and help the soil keep moist. 

Use biodegradable mulch in areas when you’re trying to grow new plants as it will break down and give the saplings and seeds a bounty of nutrients. 

Meanwhile, artificial mulch can be made with plastic, glass, gravel, stones, rubber, and even broken down CDs. 

Artificial mulch can be arranged aesthetically and be used as a garden decoration. Some types of artificial mulch contain chemicals which can help keep away pests. 

Readymade mulch is available at most outdoor and gardening stores. Still, you can also make your own mulch by gathering fallen leaves, twigs, and grass clippings from your gardening and storing them to use. 

Mark out where you want to mulch 

Mulch should always be applied around and not over a plant. Using a shovel, gently draw a line in the soil to mark out where you want your mulch to be. 

Make sure that it is not too close to any plants or buds to avoid accidentally covering them with mulch. 

Pile on the mulch 

Once you’ve marked out the area, place small piles of mulch down and then rake it out into an even layer. 

If you’re using artificial mulch, you may need to use your hands to spread it evenly. 

The layer of mulch should be between 2-4 inches; in summer, you can use less mulch. In autumn, layers should be thicker as the soil needs more protection from the cold. 

After building up a layer, spray the mulch with some water to seal it in. 

Replacing the mulch 

Replace biodegradable mulch at least once a year, but replace artificial mulch only when it appears to be wearing down. 

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While you can simply pile new organic mulch over the old, you’ll have to clear away the artificial mulch to replace it with new mulch. 

How and When to Use Compost 

Compost is just as if not more important as mulch in keeping soil healthy, allowing it to retain nutrients and helps plants absorb the nutrients. 

You should mix compost with soil when you’re planting new sapling or seeds to give them extra nutrition. You can also spread compost on top of lawns or on vegetable and flower beds. 

Unlike mulch, compost can be used at any time of the year. Use it whenever you’re establishing new plants or when you think your garden needs a boost. 

There are several steps to keep in mind when using compost. 

Copyright article owner is for this article. This post was first published on November 15, 2019.

Choose the right compost 

There are several types of compost, each of which needs to be used in a different scenario. These include: 

  • Mushroom compost. Made with waste from mushroom farming, mushroom compost is rich in nutrients and can be used to enrich the soil for any plants from seedlings to shrubs to fully-fledged trees. 
  • Seed and potting compost. This is the best compost for helping seeds begin to sprout as it has properties which help it retain moisture, 
  • Vermicompost. To make vermicompost, worms feed on food waste to create high quality, dense compost. Vermicompost can be spread over flower or vegetable beds. 

Some gardeners choose to make their own compost, which is cheaper. Homemade compost can be made using a range of organic matter, including: 

  • Fruit and vegetable scraps 
  • Grass and plant clippings
  • Newspaper
  • Cardboard 
  • Cotton cloth 
  • Wood shavings

Don’t use other food waste like meat and fish bones as it will attract pests and interfere with the breakdown of the compost. 

Store the organic waste in a sturdy container, and bacteria will start breaking the material down. In a few months, you’ll have rich, homemade compost. 

Or, build a compost pile on dry earth, topping the scraps with manure and turning the compost pile occasionally. 

If you’re new to composting, however, it’s best to buy your compost in a garden store after talking to their advisors about which type will suit your needs. 

Putting down the compost 

Adjust the way you put down compost depending on the type of plant you want the compost to benefit. 

If you want to revitalize your vegetable or flower beds, pat a two-inch layer of compost over the flower bed using a shovel. 

For potted plants, cover the soil in the pots with one inch of compost twice a year. 

If you want to fortify fully grown trees and help strengthen their roots, then place compost into the top two inches of soil up to the edge of the tree’s canopy. 

However, don’t go any deeper to place the compost. If it is to close to the roots, it may cause the roots to rot. 

And don’t place compost in holes where you’re planning on planting saplings as the saplings won’t spread their roots into regular soil, stunting their growth. 

Finally, you can spread compost across your lawn to give it some additional nutrients and help make it more vibrant. 

Some gardeners also choose to use compost as mulch, patting it down on areas that they want to fortify the soil. Compost can also help inhibit the growth of weed seeds and bad bacteria. 

Final Thoughts

Use compost and mulch in parallel to improve and protect your garden’s soil. 

ReadyToDIY is the owner of this article. This post was published on November 15, 2019.

Healthier soil will help you nurture stronger, healthier plants, which will make for a vibrant, beautiful garden!