plants for retaining walls

Hot Gardens Newsletter: Retaining Beauty

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retaining wall with agaves, crape myrtle

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, above, silvery green Helichrysum cascades over the edge. Gigantic 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 little water and they visually break up the building's blank gray 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.

retaining wall with creeping fig and grass

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 could also be used this way.

Spilling over the top of the wall is brighter green ornamental grass and, behind that, 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.

Another example of the cascading effect of grasses--this time 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 with pittosporum and hawthorne

This seemingly plain double hedge on the top of a stuccoed retaining wall combines a taller Pittosporum hedge in back and Indian Hawthorne (Rhaphiolepis indica) as the lower hedge in front. In spring the Indian Hawthorne is densely covered with bright pink blooms.

retaining wall with kangaroo paw flowers

While this red Kangaroo Paw (Anigozanthus) 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.