The Best Plants for Erosion Control: Protect Steep Slopes and Gardens

The Best Plants for Erosion Control: Protect Steep Slopes and Gardens

Soil erosion can cause significant damage to landscapes, especially on steep slopes where it is more prone to occur. However, with the right plants, you can effectively control erosion and create a beautiful and sustainable garden. In this article, we will explore some of the best plants for erosion control that thrive in various conditions such as full sun, partial shade, or even full shade.

​What Causes Soil Erosion?

Soil erosion is caused by various natural and human activities that disrupt the balance of the soil, making it more vulnerable to the removal of topsoil by agents like water, wind, or gravity. Here are some of the primary causes of soil erosion:

  1. Water Erosion:
    • Rainfall: The impact of raindrops on the soil surface can dislodge and detach soil particles, initiating erosion. The force of running water can transport these particles downhill.
    • Surface Runoff: When rainwater does not infiltrate into the soil but instead flows across the surface, it can carry away soil particles. This type of erosion is known as sheet erosion.
    • Gullies and Stream Erosion: Over time, flowing water can carve channels and gullies into the landscape, carrying away large amounts of soil.
    • Flooding: Floodwaters can result in significant soil erosion as they move swiftly and can transport large volumes of sediment.
  2. Wind Erosion:
    • Strong winds can lift and transport fine soil particles (silt and clay) into the air. These particles can be carried over long distances before settling back to the ground, often in a different location.
  3. Gravity Erosion:
    • Soil can be eroded through gravitational forces, such as landslides and rockfalls. Steep slopes, unstable soils, and heavy rainfall can contribute to gravity erosion.
  4. Human Activities:
    • Deforestation: The removal of trees and vegetation reduces the natural protection that plant cover provides against erosion. Tree roots also help bind soil together.
    • Agriculture: Practices like over-tilling, monoculture farming, and excessive irrigation can leave soil exposed and susceptible to erosion.
    • Construction and Urbanization: Building activities, road construction, and the clearing of land for development can disturb the soil and lead to erosion.
    • Mining: Excavation and mining operations can expose large areas of soil, making them vulnerable to erosion.
    • Improper Land Management: Poor land management practices, such as improper grazing, can damage vegetation cover and contribute to soil erosion.
  5. Climate Change:
    • Changes in weather patterns, including increased rainfall intensity and frequency, can exacerbate erosion in some regions.
  6. Natural Factors:
    • Natural factors like earthquakes, volcanic eruptions, and glacier movements can disturb soil and contribute to erosion.
  7. Soil Properties:
    • The type of soil plays a role in erosion susceptibility. Soils with poor structure, low organic matter content, or a high proportion of fine particles are more prone to erosion.

Soil erosion can have detrimental effects on agriculture, water quality, and the environment. Preventing and mitigating soil erosion involves implementing erosion control measures, such as planting cover crops, building terraces, using erosion-control structures, and practicing responsible land management techniques to protect and conserve the topsoil.

White flowers on wild strawberries that are planted as groundcover for erosion control in Michigan.

Wild Strawberry by D. Jarvis

Classic Signs Of Soil Erosion

Erosion in soil can have detrimental effects on your landscape and garden. It occurs when soil particles are carried away by water, wind, or other environmental factors. Here are some common signs of erosion in your soil:

  1. Soil Ruts and Channels: Erosion can create visible ruts, gullies, or channels in your soil. These are often formed by flowing water, which carves paths through the soil, carrying away particles.
  2. Exposed Roots: As soil erodes, it can expose the roots of trees, shrubs, and other plants. This can make them vulnerable to damage, drying out, or even toppling over in severe cases.
  3. Bare Spots: Erosion can lead to the loss of topsoil, leaving behind bare spots or patches in your garden or landscape. These areas may be more susceptible to weed growth and can be less productive for growing plants.
  4. Sediment Deposits: Downhill from the eroded areas, you may notice sediment deposits, often in low-lying areas. These deposits consist of the soil particles carried away by erosion and can accumulate over time.
  5. Loss of Mulch or Ground Cover: Erosion can wash away mulch, ground cover plants, or other protective materials you’ve applied to your garden. This loss of cover can further expose the soil to erosion.
  6. Soil Cracks: As soil dries out due to erosion, it may develop cracks on the surface. These cracks can further facilitate the movement of water and wind, exacerbating erosion.
  7. Decreased Plant Health: Plants in areas affected by erosion may show signs of stress, such as wilting, browning leaves, or reduced growth. This is often due to the loss of topsoil and nutrients.
  8. Muddy Runoff: After heavy rain or watering, you may notice muddy runoff flowing from your property. This indicates that soil is being carried away by water.
  9. Increased Sediment in Water Bodies: If your property is near a stream, river, or pond, you may notice an increase in sedimentation in the water. This can harm aquatic ecosystems and water quality.
  10. Exposed Rocks and Subsoil: Erosion can remove the topsoil layer, leaving behind rocks and subsoil, which may be less fertile and less suitable for plant growth.

To address erosion issues, it’s essential to take preventive measures such as installing good erosion control devices, planting erosion-resistant vegetation, and creating contour terraces or swales to slow the movement of water. Properly designed drainage systems can also help mitigate erosion problems. Additionally, maintaining ground cover, mulch, and soil stabilization techniques can help prevent and reduce soil erosion over time.

Native Plants: Excellent Choices for Erosion Control

When it comes to combatting soil erosion, native plants are an excellent choice. They have adapted to the local climate and soil types over time, making them a hardy and resilient low-maintenance plant. Native grasses with extensive root systems are particularly effective at stabilizing soil on steep slopes.

Some examples of native plants include Virginia Creeper and Wild Blue Indigo.

Ground Cover Plants: Protecting Large Areas

Ground cover plants are another great option for erosion-prone areas, especially when dealing with large areas or even construction sites. These low-growing plants form dense root systems that bind the soil together, preventing water erosion.

Wild Strawberry, Creeping Phlox, and Wild Stonecrop are popular choices for their extensive root systems and ability to thrive in both full sun and partial shade.

Ornamental Grasses: Stabilizing Steep Hillsides

For steep hillsides where erosion control is crucial, ornamental grasses offer an ideal solution. These attractive plants have a deep root system that helps anchor the soil while providing an aesthetically pleasing landscape.

Hardy grasses like Little Bluestem and Switchgrass are known for their tolerance to strong winds and dry soils.

Low-Growing Shrubs: Combating Erosion in Shady Areas

Shady areas pose unique challenges for erosion control, but there are still options available. A low-growing shrub with deep root systems can help stabilize the soil and prevent erosion even in areas with limited sunlight.

Bearberry and Gro Low Sumac are excellent choices for their adaptability to partial shade and drought-like conditions. Both of these shrubs are also native to many parts of the US.

Ground Covers and Vines: Protecting Soil on Slopes

To prevent soil erosion on slopes, ground cover plants and vines with dense root systems are invaluable. They act as natural barriers, preventing rainfall from directly hitting the soil and washing it away.

Creeping Juniper, Creeping Phlox, and Climbing Hydrangea are all excellent options for their ability to spread quickly and form a protective layer over the soil. Additionally, low-growing ground covers add visual interest and can enhance the overall beauty of the landscape.

What Makes These Plants Effective At Erosion Control?

These plants are effective at erosion control because they have specific characteristics that help prevent soil erosion:

  • Native plants are excellent choices as they are adapted to the local environment and can thrive in their natural habitat, making them more resistant to erosion.
  • Ground cover plants have a spreading growth habit, forming a dense layer that acts as a barrier against rainfall, preventing direct impact on the soil surface.
  • Ornamental grasses, with their deep root systems, help stabilize steep hillsides by holding the soil in place.
  • Low-growing shrubs are suitable for shady areas and have deep roots that anchor the soil and prevent erosion.
  • Ground covers and vines with dense root systems protect slopes by preventing rainfall from directly hitting the soil and washing it away. These plants spread quickly and form a protective layer over the soil, enhancing its stability while adding visual interest to the landscape.
Karl Foerster Grass has fast growing roots that make it a great perennial to plant in the fall with good erosion control.

Karl Foerster Grass

How To Encourage Plants To Grow Deeper Roots For Erosion Control

Encouraging plants to develop deeper roots can help them become more resilient and better able to withstand drought and other environmental stressors. Here are several techniques you can use to promote deep root growth in your plants:

  1. Choose the Right Plants: Select plant varieties that are known for developing fibrous root systems. Native plants are often well adapted to local conditions and can have deep root systems.
  2. Proper Planting Depth: When planting, make sure to place the plant at the appropriate depth in the soil. Planting too shallowly can limit root development. Follow the planting instructions for each specific plant.
  3. Water Deeply and Infrequently: Water your plants deeply and less frequently, rather than shallow and often. This encourages roots to grow deeper in dry soil in search of moisture. A deep soaking once a week is generally better than frequent shallow watering. Use a soaker hose or a drip irrigation system to deliver water slowly to the root zone.
  4. Mulch: Apply a layer of organic mulch, such as wood chips or compost, around the base of your plants. Mulch helps retain soil moisture, regulate temperature, and reduce weed competition, all of which can encourage deeper root growth.
  5. Avoid Over-Fertilizing: While nutrients are essential for plant growth, excessive fertilization can lead to shallow root development. Use a balanced fertilizer sparingly, following the recommended application rates.
  6. Loosen Soil: Ensure that the soil is well-draining and not compacted. You can use a fork or a soil aerator to loosen the soil, allowing roots to penetrate deeper.
  7. Gradual Root Zone Expansion: When establishing new plants, start with a smaller root ball or container size and gradually increase the root zone area. This encourages roots to explore and grow deeper as they search for nutrients and water.
  8. Avoid Soil Compaction: Avoid heavy foot traffic and heavy machinery on the root zones of your plants, as soil compaction can limit root growth.
  9. Prune Properly: Pruning can stimulate root growth by reducing the demand on the above-ground portion of the plant. However, be careful not to over-prune, as this can stress the plant.
  10. Monitor and Adjust: Regularly monitor the moisture levels in the soil and adjust your watering schedule accordingly. Also, keep an eye on the health of your plants and make adjustments as needed.

Remember that encouraging deeper root growth is a gradual process, and it may take some time to see significant results. Additionally, different plant species have varying root growth habits, so it’s essential to research the specific needs of the plants you are growing.

Native flowers in Michigan provide thick ground cover for landscaped areas that can also help prevent soil erosion.

Summer Flowers by R. Larue