Which plants will improve the appearance of retaining walls

Creating Beauty on Retaining Walls

low retaining wall with agave and crepe myrtle trees

This low retaining wall has been faced with brick and the area behind it filled with drought-tolerant plants which can survive some neglect. In the photo silvery green Helichrysum cascades over the edge. Gigantic upright Agaves and large Flax (Phormium) add drama. In summer the Crape Myrtle (Lagerstroemia indica) trees provide shade and white flowers to this predominantly gray-green narrow landscape at the side of a building. All the plants need very little water. They visually break up the building’s blank gray wall with big and bold plants combined with light and delicate. This look can be scaled down to work beautifully on top of a retaining wall in a home garden.

The versatile retaining wall

Retaining walls — whether they are made of poured concrete, concrete blocks, or stacked railroad ties–are often the most unloved features in a landscape. The job of these one-sided walls is to hold the earth back and keep it from crumbling or crashing into a walk, a driveway, a street, or a backyard.

Because these walls are often low, they are frequently left plain or simply have a coat of paint slapped on them. So here are a few ideas of how plants can turn a utilitarian feature into a beautiful asset in your garden.

A good rule of thumb is to layer plants by having have a few cascade over the edge, others mounding, and still others providing an upright shape on top. If the wall is tall, then you may need to either paint it or plant a climbing plant to cover it.

Layering plants

This photo shows a good way to layer plants. On this 4 foot high retaining wall at the front of a lawn, the owners have planted Creeping Fig (Ficus pumila) to grow up the wall. Creeping fig should face away from direct hot sunlight and needs regular pruning. Other climbing plants that cling to surfaces could also be used this way.

Spilling over the top of the wall is brighter green ornamental grass and, behind that on top, a low growing hedge of English Boxwood (Buxus microphylla) which encloses a traditional lawn. In desert climates Korean Boxwood is a better choice.

Grasses on top of retaining walls give a waterfall effect, especially in summer when they cascade over the edge of the wall.

As an example of the cascading effect of grasses–this Deer Grass (Muhlenbergia) drifting down over a low river rock retaining wall at the edge of a driveway. Deer Grass is very drought tolerant and easy care.

Retaining wall Indian Hawthorne pittosporum

If you prefer something more tailored and less flowing, this neat and tidy double hedge on the top of a stuccoed retaining wall combines a taller drought-tolerant Pittosporum hedge in back and Indian Hawthorne (Rhaphiolepis indica) as the lower hedge in front. In spring the Pittosporum has smallish white flowers with an amazing fragrance and Indian Hawthorne is densely covered with bright pink blooms.

Retaining wall with kangaroo paw flowers

And for a minimalist look… While this drought-tolerant, red Kangaroo Paw (Anigozanthus), left, is in essentially a raised flower bed, consider it an inspiration for the top of your retaining wall. It is a simple planting, colorful for months on end in summer and very drought tolerant. Kangaroo Paw makes a good cut flower for your home and will rebloom into Fall if you cut the stems down to the base.

For 6 other suggestions for garden walls, go here