What is Mulch and Mulching

“What is Mulch?” is a question with several answers. Technically, mulch is any loose substance which is laid over soil as a covering. Mulch can be any number of substances from compost to bark, straw to grass cuttings. There are also a number of reasons why a gardener might use mulch, as the incredibly versatile process of mulching can have all sorts of benefits for the soil and the garden.

At heart, mulching is simple enough (laying down your chosen material over your chosen patch of soil) and is most often employed to benefit the soil in some way, perhaps by helping it retain moisture, fertilise it or protect it from certain hazards.

There are some slightly different steps to the process, depending on what type of mulch you’re using (see below), but generally speaking, mulching is pretty straightforward. When using mulch around plants, which can help insulate them in cold and give a steady nutrient boost, simply be sure to keep a centimetre’s diameter around the base of your plants clear to prevent any rotting resulting from wet mulch in contact with stems. If you’re using mulch to combat weeds, two things to keep in mind are to make sure the soil is weeded before you add the mulch (you don’t want protect and nourish the weeds!) and be sure to apply a thick enough layer (usually 2 to 4 inches) to stop the weeds breaking through.

Well, it depends on what you’re aiming to achieve! Different kinds of mulch are used for different purposes and, although there are few handy principles that apply in all cases. Generally speaking, mulch will protect a layer of soil and, in the vast majority of cases, decompose. This means that mulch might have to be replaced, but it will enrich the soil with nutrients as it decomposes.

Most growing guides for plants will recommend that you mulch after planting to get the soil to optimum conditions and provide a supply of much needed nutrients. Generally speaking, the moister a mulch, and the more organic material it contains, the more nutrients it will impart to the soil and the faster it will decompose. The drier a woodier a mulch, the less nutrients it will impart, but the longer it will last. As such, this type of mulch is more often used for protection purposes, such are preventing unwanted seeding, weeds or protecting the base of plants from rooting when in contact with moist soil. Mulch can also be “dug in” to soil to alter its consistency. For poorly draining soil, for example, digging in a good amount of mulch will break it up and improve the drainage.

As you might have guessed then, mulch has all sorts of uses but the application is never difficult and the type of mulch you should use is usually pretty obvious. Yet although a straightforward garden task, mulching can reward you with real benefits in your gardening. To break things down, it’s worth going through each kind of mulch and the different things each can be used for.

Bark mulch consists of shredded or chipped pieces of tree bark. This type of mulch is dry and bulky and lasts a good deal longer than most other mulches. Due to its long life and slow decomposition, this is the type of mulch to use when you want to put down a protective layer over an area where you won’t be doing a great deal of digging (it can be a bother to move out of the way if you’re constantly planting around it). As such, use this mulch for protection around the base of trees or shrubs, or to deal with areas of weeds.

Compost is simple degraded organic material which you can easily create within a compost bin or other container. Compost is rich in nutrients and will hold a lot of moisture so it’s great for spreading a thin dressing around newly planted plants to give them a real boost.

Newspaper is a seriously versatile form of mulch and can be a real champion in several areas. For one thing, it’s one of the best for retaining moisture and it’s also pretty handy at suppressing weeds. Newspaper can be held in place and beneficially combined with other organic mulch to provide a protective layer for more delicate plants right through the growing season. When layer newspaper down bare, remember to moisten it a little to prevent it being blown away by high winds.

Straw and hay are very often used for vegetable gardens and fruit plots. The strawberry in fact gets its name from the straw which was traditionally laid down as mulch to prevent contact between the plant and moist soil, which can lead to rotting. Straw and Hay is a usually dry mulch placed down around these types of plants to prevent transmission of soil and soil-borne diseases. It also encourages friendly insects and spiders which can benefit plants in all sorts of ways.

Synthetic mulches such as black plastic and landscape fabric will not compose at all. This makes them excellent for protective purposes but does of course mean that they won’t impart any nutrients into the soil. For tackling drought and weeds, however, they do a great job and you won’t have to worry about replacing them.

At the end of the day, as you make your way as a gardener, you’ll scarcely encounter a growing or gardening guide which doesn’t mention mulch in some way. Mulching is a cornerstone of gardening, but you’ll rarely find yourself fretting over the what’s and how’s. Taking a little time to carry out this particular garden duty and you’ll be seeing the benefits in no time at all.