If you live in Henderson or Buncombe County, North Carolina, you have a front yard steep slope. And you know that landscaping can be problematic. What plants do you use to keep your slope from eroding? Plants for erosion control form mats of roots to hold the soil in place. Prairie-like drought-tolerant plants are the best hillside landscaping choices.
How do I prevent soil erosion in a hillside garden?
If you have soil erosion, you can often see a muddy mess at the bottom of a slope or steep hillside after a hard summer rain. Instead, I’ll suggest five prevention measures to keep your soil in place.
First, find a creeping ground cover for the entire area to stabilize the soil and reduce the water runoff. This helps because when the rain hits the leaves, it helps shield the earth from the impact. This layer allows the water to collect between the leaves and soak into the ground. This prevents surface runoff and carrying debris and lessens soil erosion. Groundcovers are nature’s living mulch which brings me to the next point.
Add a layer of mulch where you have yet to establish ground cover until it grows and spreads to all the surfaces. Mulch helps prevent the soil from washing off with surface water. If the mulch is also washing away, use pine needles that knit together and stay put.
Thirdly, avoid over-tilling the surface or digging excessively. The loosened soil carries it away with the first downpour.
Next, choose plants with deep rooting systems that spread and can anchor the soil in place. Avoid planting around septic systems or drainage areas. These areas could damage the roots or the costly systems.
Finally, want more usable space? Consider adding terraces with retaining walls to reduce the steepness of the slope. This earth movement allows the water to soak into the soil instead of running downhill. Making the land more accessible means greater enjoyment and easier gardening reach.
Implementing these measures can help prevent soil erosion. That way, your hillside garden and ensure the soil stays on your side of the road!
Understanding plant placement on a steep slope
Water will flow down the hill when it rains, carrying nutrients and soil. Planting the right plants in the right places is crucial to erosion control on hillsides. At the top of the slope, the soil will dry out faster. It’s best to plant drought-tolerant plants that can handle the heat and lack of moisture. In the middle of the slope, there is medium moisture. You can grow plants requiring moderate water and tolerate moisture fluctuation. Water will accumulate, and the soil will be wetter at the bottom of the slope. Plant water-tolerant plants that can handle excess moisture. These plants can also help to absorb excess water and prevent erosion. By understanding the water flow, you can place plants in the correct place.
What grasses are suitable for landscaping on a steep slope?
Several plants are adaptable to our terrain in Henderson and Buncombe counties. Here are a few of the best plants for landscaping on steep slopes in zone 7:
These ornamental grasses are suitable for dry shade under thirsty trees. This includes Striped Tuber Oat Grass (Arrhenatherum elatius subsp. bulbosum ‘Variegatum’). Its green and white variegated leaf is 8-12 inches tall and lightens up a shady spot.
- Appalachian Sedge (Carex appalachica) grows 10-12 inches in height. Carex can handle part shade (morning sun) to full shade (2-4 hours of sun). This Carex is great for a no-mow area, but you still want to have the grass texture.
- Everillo Sedge (Carex oshimensis ‘Everillo’) is striking in her lime green. She progresses to a bright yellow the more sun rays she gets on her leaves. While she prefers shade, she can handle the morning sun in cooler climates. She likes to be in moist, well-draining soils. But this grass can tolerate dry spots after establishment.
- Add Blackhawks Big Bluestem (Andropogon gerardii ‘Blackhawks’) to the dry to the average moisture-sloped yard. The red to purple color grass grows 1.5-5 feet tall and tolerates our clay conditions in WNC. Another bonus is he attracts pollinators, and deer avoid it. Two prizes in one!
Planting Steep Slopes with Perennials
- Bergenia is a low-maintenance perennial that has thick, leathery leaves. The thicker a leaf is, the more drought-tolerant it is. Wooded dry shade areas will welcome this plant and give great color in the fall and blooms in the spring.
- Sedums are drought-tolerant ground covers. They can fill bare spots on your slope and help prevent erosion.
- Lavender is a low-maintenance perennial that loves hot, sunny spots. It’s perfect for adding a pop of color to your slope. Lavender is native to the Mediterranean, has rocky soil, and is drought tolerant. Placing this plant on a hillside gives it the drainage it desires.
- Vinca is a low-growing ground cover that can help keep weeds and erosion at bay. Its blue flowers add a pop against the deep green evergreen foliage, and rabbits nor deer prefer it.
- Grasses, bergenia, sedum, and vinca all form mats of roots that can help with soil erosion.
Shrubs for Your Hillside Garden
If you want to add more structure to your landscape slope, shrubs are a great option. Many are low maintenance and can help with erosion control. Here are a few options to consider:
- Viburnum spp. comes in both evergreen and deciduous varieties. They show off brilliant fall foliage in orange, red, and yellow. Some are fragrant and can be a delight 100 feet away. Use viburnum as a natural hedge and in drifts or as a specimen.
- Beautyberry is a low-maintenance shrub that grows 3-6 feet tall. You will enjoy the stunning purple berries in the fall. It prefers part shade and well-draining soil. The roots hold back soil as they have a
combination root system of deep penetrating roots and a taproot.
- Sumacs grow in dry areas or rocky slopes and are deciduous. Their fall color ranges from yellow and orange to red, with berries of the same colors. They are excellent low groundcovers and slope stabilizers. They have a deep and extensive root system to access water and nutrients.
- Serviceberry (Amelanchier spp.) trees have deep, fibrous roots that help anchor the slopes. They also have the added benefit of producing edible berries in the spring.
- Red osier dogwood (Cornus sericea) is a deciduous shrub with a deep root system. It also has striking red bark that provides year-round interest in the garden. The stems show up beautifully next to newly fallen snow!
- Buttonbush (Cephalanthus occidentalis) is a native shrub. Its deep root system is ideal for stabilizing wet areas or stream banks. It produces spherical, white flowers that are attractive to pollinators.
- Forsythia (Forsythia spp.) is a fast-growing shrub with deep roots that can help stabilize slopes. It produces bright yellow flowers in the spring that are a welcome sight after a long winter.
Landscaping a garden on a hillside can be challenging. But with the right plants and maintenance, you can transform the area. The plants mentioned need minimal watering and upkeep, and their root systems can help prevent soil erosion. These shrubs will add structure and color to your landscape. Additionally, soil erosion will not be an issue.
Prevent Soil Erosion with These Extra Steps
It’s essential to minimize foot traffic as much as possible when gardening on a steep slope. Foot traffic can further erode the soil and damage the plants. Consider adding a path or stepping stones to guide foot traffic and prevent damage to your plants. Another tip is to use a mulch or gravel layer around your plants. This layer helps retain moisture in the soil and prevents weeds from taking over the area. It also provides an additional layer of erosion control. Finally, periodic inspection of your slope garden is crucial. Check for any signs of erosion, such as bare soil or exposed roots, and address them immediately to prevent further damage.
Creating a low-maintenance garden on a steep slope requires careful plant selection. Plants that are suitable for the environment and can fill in and hold the soil with deep roots can also prevent weeds from growing. As a result, groundcovers and mulches play a vital role in weed control on a steep hillside garden.
How do I prepare the soil on a hillside for gardening?
Preparing the soil on a hillside for gardening can be challenging, but with proper techniques, it will set your garden up for success. The first step is to assess the soil’s condition and determine if it needs amendments such as compost, fertilizer, or lime. Soil testing kits are available at most garden centers, or you can send a sample to a soil testing laboratory for a more comprehensive analysis. Once you have determined the soil’s needs, the next step is to prevent soil erosion, as stated previously. Create a contour system or terrace the slope. A contouring system involves creating small ridges or berms. When designing, follow the natural curves of the hill to help slow down water movement. Terracing involves creating flat areas on the slope. Building retaining walls to support those areas also helps with erosion. After amending the soil and erosion prevention measures are in place, it’s time to plant!
What is the best way to water plants on a hillside garden?
Watering plants on a hillside garden can be tricky, as water tends to run off quickly and not soak into the soil as easily. A drip irrigation system is one of the best ways to water plants on a hillside garden. Drip irrigation allows water to be slowly released directly to the plant’s roots, reducing evaporation and runoff. Another option is to use a soaker hose, a porous hose that allows water to seep slowly and directly into the soil. Set both options up with a timer to ensure consistent watering and avoid under or over-watering. Hand watering can also be adequate, but it may require more effort and attention to ensure all plants get enough water. It will also involve more time and dragging a hose around. Accessing a steep slope can be challenging, so I recommend the first two suggestions! Regardless of your chosen method, water deeply and infrequently. This method will encourage healthy root growth and prevent water waste. Follow my instructions on Best Practices for Watering New Plants.
Do’s & Don’ts of Hillside Gardening
Hillside gardening can be a challenging but rewarding experience. However, some common mistakes that homeowners make can lead to problems such as erosion, soil depletion, and plant damage.
Many homeowners get excited about installing a new or improved garden. They jump into clearing the land before they have a landscape design plan. Without a plan, you may have a garden that doesn’t work well with the slope. Erosion or runoff issues start happening.
Not all plants are best for hillside gardening. Some may need help to handle the slope or the soil conditions. Others may be too aggressive and spread too quickly. Hire a landscape designer who can help you avoid costly mistakes. Choose plants that suit your specific slope and soil conditions. Instead, clear the land only a week or two before you plant so there is little time for erosion.
If retaining walls are the best choice at that time, large boulders can hold up the terracing. Native rock is an excellent choice for use in hardscaping. Install hillside steps or pathways next. Level pathways and tier gardening can make pruning or cutting flowers easier. Planting will come next, then setting up the watering system immediately after installation. Until the irrigation works, someone must hand water to keep the plants healthy.
Before Going Out to Garden on a Slope
Before starting any hillside gardening project, there are some tools and considerations that you should have in mind. First, keep your garden tools handy in a backpack. Think about all the tools you’ll need before starting and have them out, clean and ready. A wheelbarrow or cart to carry all the tools and bags of soil amendments is handy to avoid extra trips. A water bottle, cell phone, and sunscreen will help too! Wearing boots with cleats can help stabilize and balance yourself in rough places.
Hillsides can be dangerous to work on, so ensure you have proper footing and wear appropriate shoes. Work with someone to avoid accidents, and use a ladder on a flat surface to reach higher areas.
How do I deal with pests and diseases in a hillside garden?
Practice proper sanitation to deal with pests and diseases in a hillside garden. Remove dead, damaged, or diseased plant material. Do not work in the garden after rain or when the leaves are wet. When the garden is damp, fungus and diseases can spread. After using your tools, wash them with soap, water, or bleach to disinfect them.
Additionally, selecting disease-resistant plant varieties. Organic pest control methods can help prevent and manage pest and disease issues. Inspect the leaves, stems, and undersides to look for lurking pests. They can be hatching eggs or nibbling on the tender parts of the plant. Cleaning up after a pest infestation can prevent other plants from getting attacked.
Another way to prevent pests and diseases is to plant companion plants that naturally repel pests. For example, planting marigolds alongside your vegetables can keep nematodes away. Planting garlic or chives can keep aphids at bay. Using organic fertilizers and avoiding over-fertilizing can help prevent pest and disease issues. Over-fertilization can cause plants to be more susceptible to pests and diseases. They can also harm beneficial insects like earthworms. These tips can enhance your steep slope landscape while keeping it healthy and pest-free.
Remember to plan ahead when working in the garden. Have the right tools, and take safety precautions while working on your slope. With a little effort and care, you can transform your hillside garden into a stunning and thriving landscape.
Schedule an appointment with a garden designer
Call me to schedule an appointment if you are dealing with what to put on your steep slope to enhance the appeal or control erosion. I’ll talk to you about your vision, make suggestions and present a plan you’ll love with low-maintenance options!