Slope gardens

The right landscaping reduces runoff and erosion

Don’t remove grass or plants until you are ready to replace them; their roots are likely stabilizing the soil.

Consider sun, shade, and moisture before choosing plants or changing your landscaping. Any changes you make will affect drainage.

Secure rocks or stones in the slope and plant around them to slow the flow of rainwater.

Consult a professional about installing retaining walls to divide the slope into garden beds (like large steps).

Use drought-tolerant plants near the top of the slope and put plants that prefer wet soil near the bottom. See the sample garden designs for suggested plants.

Use a mix of trees, shrubs, perennials and ground covers plants to intercept rainfall.

When adding a new plant, build up the soil underneath it to slow and absorb rainwater.

Use a 7 centimetre (3 inch) layer of mulch between plants to further reduce runoff and retain moisture. You may need to experiment with different types of mulch to find material that stays in place.

For the first few weeks, keep the top 2.5 centimetres (1 inch) of soil moist. After that, water once a week until plants are established (one to two seasons). Then plants should thrive with average rainfall.

Add 5 centimetres (2 inches) of organic material (e.g. compost, manure, leaf mold) every two years to fertilize and create a heavier soil that resists erosion. Use even more organic material if the soil is sandy and light.

Slope garden design—full sun

At least six hours of direct sunlight a day

Slope plants full sun

Spring interest

  • Aurinia saxatilis, basket-of-gold
  • Iberis sempervirens, candytuft
  • Lavandula angustifolia, lavender
  • Phlox subulata, creeping phlox
  • Salvia officinalis, common sage

Summer interest

  • Arctostaphylos Uva-ursi, kinnickinnick
  • Echinops sphaerocephalus, globe thistle
  • Hemerocallis species, daylily
  • Monarda didyma, bee balm
  • Thymus serpyllum, creeping thyme

Fall interest

  • Calamagrostis species, feather reed grass (can be invasive)
  • Gaillardia species, blanket flower
  • Geranium maculatum, wild geranium
  • Juniperus horizontalis, creeping juniper
  • Rhus aromatica, fragrant sumac

Printer-friendly: Sun – slope garden

Slope garden design—shade

Less than three hours of direct sunlight a day, with filtered sunlight during the rest of the day.

Slope plants shade

Spring interest

  • Anemone species, windflower
  • Asarum species, wild ginger
  • Cornus canadensis, bunchberry
  • Polygonatum species, Solomon’s seal
  • Rhus aromatica, fragrant sumac

Summer interest

  • Aruncus dioicus, dwarf goat’s beard
  • Bergenia species, elephant-eared saxifrage
  • Campanula rotundifolia, harebell
  • Heuchera species, coral bells
  • Hosta species, plantain lilies

Fall interest

  • Adiantum pedatum, northern maidenhair fern
  • Deschampsia species, tufted hair grass
  • Epimedium species, barrenwort
  • Hakonechloa macra ‘Aureola’, Hakone grass
  • Pachysandra species, Japanese spurge

Printer-friendly: Shade – slope garden