If you notice that the topsoil in your garden is thinning, then you may have a problem with soil erosion. Left unchecked, soil erosion will prevent your garden from producing the fruits and vegetables that you are hoping for.
So, how do you prevent soil erosion? Planting cover crops such as grass, shrubs, and trees will prevent wind and water from removing soil from your garden. A wind break, such as a wall or hedge, will prevent soil erosion due to wind. Using irrigation, crop rotation, composting, and mulching will prevent your soil from thinning and being carried away by water.
Before we get into the details on how to prevent soil erosion, let’s take a quick look at what soil erosion is, and what causes it.
What is Soil Erosion?
When we talk about soil erosion, we mean that soil is carried away over time by natural means (wind and water) or artificial means (farming and gardening). When soil erosion occurs, the top layer of soil (called topsoil) becomes thinner.
Over time, this thinning of the topsoil prevents plants from growing. The reason is that topsoil contains all of the nutrients and beneficial bacteria that are necessary for plant life.
What Causes Soil Erosion?
As mentioned earlier, the main causes of soil erosion are wind, water, farming, and gardening.
Soil Erosion Caused By Wind
When soil is dry and barren, with nothing growing in it, the wind can easily blow it away. Soil that is too acidic or alkaline may prevent anything from growing in it, which can eventually lead to soil erosion.
If you think your soil may have a problem, you should do a soil test as the first step. For more information, check out my article on how to do a soil test.
Soil that is out in the open, unprotected by walls, trees, or shrubs, is also more likely to be blown away by the wind.
Soil Erosion Caused By Water
The same type of dry and barren soil mentioned above is also vulnerable to soil erosion caused by water. Heavy rainstorms and flooding, improper watering, and poor irrigation or drainage can all contribute to soil erosion.
As if soil erosion caused by water weren’t bad enough, there is also the problem of agricultural runoff. This means that soil washed away by rain or irrigation may contaminate nearby lakes or groundwater, since it may contain chemical fertilizers, pesticides, or herbicides.
Soil Erosion Caused By Plants
Plants themselves can also contribute to thinning topsoil, since plants use up nutrients and organic matter from the soil as they grow. Over time, removing this organic material from the soil without replacement will lead to thin soil, which is more likely to be carried away by water or air.
Remember that if your garden is on a hill, erosion will be even worse, and will happen at a faster rate. The steeper the slope, the more you will need to worry about soil erosion.
How To Prevent Soil Erosion
There are many ways to prevent soil erosion, and some of these can be used together to maximize the chance that your soil will stay where it belongs – in your garden! Let’s get started.
Plant Cover Crops
Cover crops are planted in a garden to hold soil in place and prevent it from being blown away by wind or washed away by water. Many cover crops also have the added benefit of restoring nutrients to the soil.
For instance, alfalfa is a cover crop that restores nitrogen in the soil. Other common cover crops are winter rye and peas.
You can also plant shrubs or trees to help hold soil in place. As an added benefit, these taller plants will provide shade, which prevents soil from drying out in the summer sun and heat. If you plan properly, you can use your shrubs as a wind break to provide further protection against soil erosion.
Build a Wind Break
A wind break is anything that slows down the wind and prevents it from damaging the plants or soil in your garden. For instance, you could build a wall or plant a hedgerow (a row of shrubs or bushes) as a windbreak.
For more information, check out my article on how to protect your plants from wind and storms.
Practice Good Soil Management
If the soil in your garden is healthy, then it is more likely to stay in place, despite pressure from wind and water. Here are some ways to improve the health of your soil.
Replace Organic Material
As mentioned earlier, the plants in your garden will naturally deplete organic material and nutrients in the soil as they grow. To replace this spent organic material, you should mix compost into your soil.
The organic material provided by compost also helps to improve drainage in clay soils, and helps to retain water in sandy soils. This reduces the chance that soil is washed away by water or blown away by wind.
You can buy compost online or at a garden center, or you can make your own. Compost can be made from grass clippings, fallen leaves, dead plants, sawdust, fruit and vegetable scraps, and more.
For more information, check out my article on how to make compost.
You can also use manure (animal waste and bedding) to replace organic material in your garden. Just make sure it is composted (completely broken down) before adding it to your garden!
You can get manure from animals that you keep (not dogs, cats, or pigs!), or you can ask friends or neighbors who keep animals. For more information, check out my article on how to find sources for manure.
Another way to keep your soil healthy is to use mulch, which is any material spread over the top of your soil to kill weeds and retain moisture. An additional benefit of mulch is that it will weigh down the soil and prevent it from blowing away.
As long as the mulch itself is heavy enough, it won’t be easy for wind and water to move it away. Mulch can be made of wood chips, grass clippings, or even compost. For more information on when to use each, check out my article on mulch vs compost.
Use Crop Rotation
Over time, planting the same crop in the same area every year will deplete certain nutrients in the soil at that location. Eventually, nothing will be able to grow there, and soil erosion is much more likely to occur.
To prevent this, use crop rotation. Crop rotation means that you alternate between different crops in an area each year. For instance, you plant tomatoes in the first year, lettuce the second year, peas the third year, and onions the fourth year. After that, start the cycle all over again.
As an added benefit, crop rotation also helps to prevent plant diseases and pests from taking hold in your garden soil.
Keep Soil Moist, But Not Soaked
Soil that is very dry is easily blown away by wind. On the other hand, soil that is too wet is prone to be washed away by a sudden heavy thunderstorm. You want to achieve balance with moisture levels in your soil.
One way to do this is to use drip irrigation, instead of a handheld hose or sprinkler. With drip irrigation, you can control the amount of water your plants receive without washing away soil with excess water.
To prevent storm water from washing away your soil, you can try to capture rainwater using barrels. If you notice that certain parts of your garden are prone to flooding, then use drains or pipes to divert water from those areas.
If you have trouble with dry soil, check out my article on how to treat dry soil.
If you have trouble with wet soil, check out my article on how to make soil drain better.
Soil will be healthier if it has proper aeration. This simply means that there is enough air (specifically, oxygen) in the soil so that plants can absorb water easily.
Avoid tilling your garden if possible – it kills and disturbs earthworms. Use a pitchfork or aeration tool instead.
Preventing Soil Erosion If Your Yard Is Sloped
As mentioned earlier, soil erosion will be worse and will happen faster if your yard is sloped. In that case, you can try building retaining walls or terraces at intervals as you go down the slope. This will help to prevent soil from washing down the hill.
You can also try to build a raised bed on a slope, although it may take a little more engineering than a raised bed build on flat ground!
By now, you should have a good idea of some steps you can take to prevent soil erosion in your garden. It’s time to get out there and take action today so you can have a greener garden tomorrow!
Hopefully, you found this article helpful. If you have any questions or advice of your own on how to prevent soil erosion, please leave a comment below.