What is Mulch?

Mulch is a gardener’s best friend, whether you’re growing indoor plants or creating a full outdoor garden. Most people who have dabbled in any kind of growing will have at least heard of mulch before – but that doesn’t mean they know exactly what it is or how it works. Here’s a quick rundown of everything you should know about using mulch in your garden.

What is it?

Mulch is a blanket term for any material that gets laid over the soil, usually as a covering. There’s a vast range of mulch you can use, and almost any organic material can serve as mulch in one way or another. Common types include wood (either strips of bark, shredded wood, or woodchips), grass clippings, newspapers, leaves, and even straw. Organic mulches like these will slowly improve the soil beneath them, adding more nutrients as they decompose.

Artificial mulches are also a common option, although they’re created differently. These types can include stone and gravel, black plastic, and even landscape fabric. They don’t add anything to the soil as they decompose, but they last longer, meaning they can be useful for specific purposes unrelated to the soil’s quality.

What is it for?

Organic mulch and inorganic mulch both have one goal in common: to help the soil retain moisture and prevent weeds from growing. A good amount of mulch, especially mulch that’s already moist, will help a plant retain water for longer by ensuring the soil doesn’t dry out. Since weeds are often a surface-level hassle, mulch can smother them, preventing them from growing properly and often killing them early on.

As mentioned earlier, organic mulches can also feed plants by adding more nutrients to the soil. For example, as hay mulch decomposes, it will give the plants organic material to use as food. Inorganic mulches can’t do this, and some might even hurt the plant if they’re allowed to decompose fully, but they’re a better solution for keeping weeds dead and moisture high.

Which Should I Use?

There’s a long list of potential mulch types you might end up using, but some are better than others in specific situations. Options you might consider include:

Grass Clippings

Grass clippings is one of the most varied options – some clippings are good, some are bad. Certain grass types decompose rapidly and can end up being very smelly, while others are more like straw and won’t vanish quickly. This mulch is good for remote areas where weed suppression is important. Anybody with a garden will have an almost limitless supply of clippings.

Bark

Bark can be harder to get hold of since you have to strip it off a tree or otherwise buy it in a pre-made form. It works well around areas where you don’t need to plant anything new for a while. This mulch lasts a long time but doesn’t mix into the soil well, so moving the bark can be annoying every time you grow something new. For established gardens, though, this is one of the best options.

Newspaper

Newspaper with organic dye can be a good way of suppressing weeds, controlling the temperature of the soil, and smothering grass. Ideally, you should use the paper in layers of between four to eight sheets, then moisten them once in place. Covering the newspaper with a second type of organic mulch can improve its weed protection capabilities even further.

Straw

Straw, and by extension hay, is quite popular for gardens full of vegetables. It prevents soil-related diseases from harming your plants and keeps paths from getting as muddy after wet weather. As a side note, straw is a good home for beneficial creatures such as spiders and insects, keeping the pest population lower. Given that you can easily rake it back up or squish it into the soil, it doesn’t take much effort to dispose of.

Leaves

Shredded leaves are one of the most popular mulch types overall. You can get them almost anywhere and use them in any garden. They generally blend in well, especially in areas full of trees. However, if they’re not shredded, they can mat together and actually repel water. This makes them useful in some instances, but not in most. It may be worth investing in a good leaf mulcher if you have an abundance of leaves in your garden.

Plastic

Plastic can get very hot in the summer. This might harm your plants if you don’t keep them moist, but it can also be perfect for killing weeds and managing how much water reaches your garden. In extremely wet areas, plastic sheets with good drainage can dramatically cut down on over-watering, and they will last a long time compared to most other options.

Stone and Gravel

Stone is hard to remove, but it can manage heat and water really well if used correctly. And it also looks aesthetically pleasing! While stones can get hot, they’re not as heat-sensitive as plastic, and they also won’t smother the plants you’re trying to grow. Gravel is an easy mulch to move later on, and only a handful of rock types will ever decompose in your lifetime.