Soil cover is a concern for all gardeners because it is fundamental on so many levels. It is enough to take a walk in the forest, for example, to see the richness of the soil which, of course, is never bare. Nature doing things very well, we can be inspired by it so that the cultivable land is protected all year round, but also naturally nourished and therefore fertile, capable of meeting all the needs of future plantations. Let’s shine a spotlight on what is called mulch or mulchwithout failing to make a point on their advantages and, if any, their disadvantages.
Covering the soil in the garden: advantages and disadvantages
A bare earth is exposed toerosionau leaching by rainwater, which also promotes the escape of soluble particles or the phenomenon of leaching but not only ! In the garden, the earth must therefore be protected. The cover has multiple benefitsto know :
- Limit the compaction of the earth or slapping of the soil during heavy rains, the mulch acting as a shock absorber,
- Slow down the development of weeds by depriving them of light. These are local grasses with spontaneous development which are wrongly called “weeds” and which are classified as undesirable.
- Reduce the time spent on hoeing.
- Keep the soil cool by slowing the evaporation process, allowing less frequent watering. This therefore limits the risk of damage that can be caused by drought.
- Allow rain or irrigation water to be redistributed more gradually.
- Protect plants against the cold in winter and the heat in summer since a mulch acts as an insulator.
- Reduce the drying effect of the wind.
- Retain the heat of the day and therefore limit thermal shocks when the nights are cool. It is also said that mulch acts as a thermal buffer.
- Slow the progression of gastropods, so that young leaves are protected, which are very fond of slugs and snails.
- Preserve but also promote soil life by protecting all crop auxiliaries. In other words, allow the development of a certain fauna.
- Recycle green waste when used as mulch.
- Fertilize the land since many of the materials used to cover the ground turn into fertilizer as they decompose.
- Keep fruits and vegetables clean since they are not splashed by rain or irrigation water and this minimizes the risk of them being damaged because they are no longer in direct contact with the ground. Opting for mulching can therefore, consequently, reduce the risk of fungal diseases or cryptogamic diseases.
- Allow the gardener to use fewer products such as fertilizers, antifungals and others.
- Overall reduce the time devoted to garden maintenance.
Opt for ground cover when it is already cultivated is a solution adopted by countless gardeners. In some cases, the assets that we have just reviewed benefit in the vast majority of cases vegetable plants, shrubs, ornamental plants… In addition, depending on the solution chosen, you can take advantage of its decorative look.
Note that, even if it is often said that a good hoeing is worth two waterings, it is not recommended to abuse the hoe to which we can prefer mulching when we opt for a solution that does not does not alter the structure of the soil except to improve it. Hoeing is perfect when you want to break the crust of dry earth or weed at the foot of a few plants. But it is not recommended when it comes to treating a large garden area where mulch is more suitable.
As to disadvantages of mulchthey are far fewer than its strengths. But they should not be overlooked. The main criticisms that can be made of a ground cover in the garden are the following.
- Some plants should not be used as mulch because they negatively impact soil life. This is the case of thujafrom horsetailfrom pin or even the fern, certainly renowned for their antifungal properties (we also make liquid manure or decoctions to treat plants). But they end up destroying the activity of all the fungi by acidifying the soil. However, like the mycorhizes for example, many such organisms are very useful for good soil health.
- The mulch can retain too much water and promote the smothering of microfauna or even lead to the rotting of the root system of many plants. This is a phenomenon that can be encountered during a particularly rainy period if the ground is covered.
- Le mulch not suitable for recent sowing. It is necessary to wait at least 2 to 3 weeks before mulching the young plants.
- It is not recommended to mulch plants that are sensitive to humidity.
- Covering the soil prevents plants from self-sowing.
Finally, note that you should never mulch the garden too early because the earth must be able to warm up sufficiently under the spring sun.
How to cover the ground in the garden?
There are three main families of covers for the ground in the garden:
- Mulches of vegetable origin : they are clearly preferred in any type of garden as their assets are numerous. But it is useful to know how to choose the plants used to compose a mulch.
- Mineral mulches : if they keep the soil cool and also insulate it against cold and heat, they are on the other hand incapable of nourishing the earth since they do not decompose. They are preferably used in an ornamental garden in order to hide a protective film of the geotextile fabric type, for example.
- Artificial mulches : as it is not natural to use them to cover the ground in the garden because it is not their role at all, these mulches are qualified as artificial. We can forget them because they are of no interest.
Before opting for one or the other of these solutions, let’s take stock of all their specificities.
Plant waste
This category includes:
- Dead leaves,
- lawn mowing,
- linen sequins,
- Hemp,
- The bark,
- Straw,
- The Miscanthus,
- cocoa beans,
- walnut shells,
- fruit pits,
- Shredded young ligneous twigs or deciduous branches (this is called Ramial Fragmented Wood or BRF),
- The waste generated by the maintenance of the garden such as the size of the plants for example provided that they are healthy,
- Kitchen waste such as peelings, eggshells…
All these elements serving as natural mulch decompose and therefore contribute to the fertilization of the earth. These are the most ecological and the most economic. No wonder they are so popular.
Mineral mulches
These are mulches composed of materials which, unlike plant mulches, do not undergo decomposition processes. They are the ones we choose to bring a decorative touch in the garden because today we have a panel of colors of the richest. But in addition to enhancing the plants and more generally the garden at the aesthetic level, a mineral mulch has some advantages that benefit the plantations.
In this category, we find among others:
- The sand,
- The stones,
- The gravel,
- The pebbles,
- The pebbles,
- crushed tile,
- slate debris,
- brick pieces,
- Pozzolan…
It should be noted, however, that it is difficult to work the soil once the mineral mulch has been installed. It is not suitable for the vegetable garden, nor for flower beds, but is ideal in a rock garden or a dry garden.
Artificial mulches
They are not recommended since in addition to being unsightlythey don’t have no beneficial effect on the ecosystem. These are for example:
- burlap,
- Cardboard,
- Plastic…
It is therefore better to opt for another category of mulch.
A small special mention, however, for the forcing veil which turns out very useful over a short period. For example, it can be placed in the vegetable garden to protect a seedbed against the heat and lack of watering if you have to go on vacation for one or two weeks.
A mulch suitable for cultivated plants
Before covering the ground of the garden, it is obviously essential to wonder about the plants that this will necessarily impact. Some don’t like having their feet covered, as is the case, for example, withailof the’shallotof the’onionand more generally all plants that tolerate humidity very badly. It is quite logical. At most, we can content ourselves with offering them a very dry mulchto know straw because it is light, airy and does not ferment. For it to provide excellent protection against low temperatures, it must be placed at the foot of the plants in a thick layer.
We see how much it is necessary to wonder about the type of mulch best suited to the plants that we cultivate. The difficulty therefore consists in finding a covering solution for each type of plant knowing that if the wrong choice is made, many plants can suffer.
Cover the soil with healthy mulch
In any case, it should be remembered that in the vegetable garden, any ground cover made of a material that has been treated with a toxic and/or polluting product that will always end up penetrating the ground is prohibited. An old palette repainted with different layers of paint or varnished should never be crushed to make a mulch! Similarly, not all plant debris can be used to cover the ground of a garden. This is the case of plants that have been pruned because they were colonized by parasites or infected by a disease. It’s necessary use common sense in order to avoid contaminating all its plantations.
Finally, the gardener should not hesitate to vary the waste which will make up its mulch. In this way he obtains a natural material which, by decomposing, will bring great diversity of nutrients soil, which is essential for the good health and perfect development of plants.
What about ground cover plants?
It is an excellent solution to cover certain areas of the garden with ground cover plants. This avoids leaving the earth bare and allows you to take advantage of their ornamental effect. In this way, weeding quickly becomes unnecessary, the soil is protected and the water no longer runs off. Be careful, however, not to install them too close to the vegetable garden or the beds in which you want to plant other types of plants because the ground covers become invasive after some time…
It remains to choose them carefully, depending on the climate, the exposure, the type of soil… There are some for dry gardens, very shaded, semi-shaded or very sunny areas, cool soils, long flowering, decorative foliage…