Retaining walls have come a long way in the past couple of decades, going from simple cinder block or concrete one-dimensional structures to elaborately engineered, multi-dimensional hardscapes with style options to fit every aesthetic. While the need to cover up unsightly walls may not exist like it used to, training plants to cascade over walls is still a practice enjoyed by many for a new reason: visual interest. The mixture of hard and soft elements has become a popular design trend and no space offers more opportunity to experiment with contrasting design elements than a yard or garden.
A cluster of pink hydrangea blooms cascading over an old retaining wall shows that even the unexpected can have beautiful results.
Here are 15 cascading plants that can add a beautiful and interesting softness to any style of retaining wall.
In addition to moderately moist, the quickly-spreading Mexican Fleabane likes soil that is fertile and well-draining.
Mexican Fleabane (Erigeron karvinskianus), also known as Santa Barbara daisy or Spanish daisy, is favored for its daisy-like blooms and closely resembles its relative, the true daisy. It is a fast-growing, colorful groundcover commonly used in rocky crevices and spilling over walls. Look for a hybrid variety, which are more beautiful and refined than their standard relatives.
Grow from seed, and place the seeds near the top of the wall and in the wall cracks. This will produce a blanket of eye-catching blooms. Plant in locations that receive 6 or more hours of daily direct sun. Though not ideal, they can survive in partial shade, meaning they should still get at least 2 hours of direct sun.
Seedlings and immature plants require regular, moderate watering until they are established, at which time they are drought tolerant. Soil should not be allowed to dry out, especially in summer; rather, keep it moderately moist. The same care should be given to ensuring overwatering does not occur in the winter.
Cold hardy to USDA zone 5, Mexican Fleabane will attract bees, butterflies, and other pollinators to your garden; they are also deer resistant.
Ice Plant (Delosperma)
Delosperma plants, once established, are exceptionally heat and drought tolerant.
Another daisy-like cascading plant on our list is the cold hardy ice plant, also referred to as Delosperma. There are well over one hundred different species of succulent plants in the Delosperma genus, and the differences between them are largely leaf and flower sizes, and flower color patterns. Established plants are extremely drought tolerant.
Start with immature specimens from your nursery and plant in a sunny location. In colder climates, plant by mid-summer so they have time to establish before winter’s arrival. A frost blanket is needed in snowy conditions. In hot climates such as the Southwest US, planting in the fall is recommended.
Plant in sand, sandy loam, or gravel-heavy soil to ensure the best and fastest drainage. Garden loam is also an option in drier climates. Regardless of location, clay should be avoided. If plants begin to look stunted or sickly, you might be overwatering and/or the soil is staying too wet for too long.
Their superb heat and drought tolerance notwithstanding, Delosperma still need to be watered weekly during the peak heat of summer. At all other times they can be watered sparsely.
Aubrieta (Rock Cress)
Aubrieta blooms typically do not appear until at least their second year.
Aubrieta deltoidea – commonly known as rock cress plants, purple rock cress, or aubrieta – are beautiful, cascading plants that grow well from seed, establish easily, are one of the earliest spring bloomers, and require little water. It should be noted that flowers in the first growing season are rare and the bloom for which this species is known generally does not occur until the following year.
Aubrieta is a perennial hardy in USDA zones 4 – 8. You can either start from seed in early spring, keeping indoors for about four to eight weeks before planting outdoors. Seedlings should not be planted until after the last frost of the season.
You can also sow seeds directly into thes soil. Clear the chosen area of all debris and turn the top six inches of soil. Drop seeds on the surface and water very gently. It is important not to drown the seeds or push them deep into the soil. The area should remain moistened, but not soggy. Once established, they are incredibly drought tolerant and can easily take the full sun and high heat conditions of hardscape areas.
As is the case with most profuse bloomers, aubrieta cascading plants love the sun. They can survive partial shade but take note that they will not bloom as profusely. Soil should be well-draining and free of clay. Though not required, they also prefer growing sites rich in lime. As long as drainage is good and soil is not kept too wet, these cascading plants have no disease or pest issues.
Ivy geranium do not have the same heat and drought tolerance as standard geranium, and their care requirements are different.
Pelargonium peltatum – commonly known as ivy geranium, ivy-leaf geranium, or trailing geranium – is a tender perennial known for beautifully patterned ivy-shaped leaves and cheery, fragrant blooms in a range of appealing colors.
Ivy geraniums are generally used as annuals (except in areas with tropical climates; they are cold hardy to USDA zones 10-12). They like mild temperatures, require partial shade if heat exceeds 85-degrees, and must be kept consistently moist. Do not expect the same tolerance of hot, dry conditions that you’d find with standard geraniums.
Soil conditions should promote good drainage and root aeration, so a loamy or sandy loam growing medium is ideal. If your growing area does not have this kind of soil, amend it before planting by adding sand or perlite.
Watering should occur regularly and consistently, but only water enough to moisten. Ivy geraniums do not tolerate soggy conditions so allow the surface to dry out between waterings. Every two weeks, feed these cascading plants with a soluble plant food when watering (follow the instructions on the label).
If you are a gardener who likes options, ivy geraniums will not disappoint. There are countless cultivars and varieties available and new ones are introduced every year. This extends beyond unique foliage patterns and bloom colors; there are compact and dwarf varieties, and even hybrid crosses with zonal geraniums.
To clean, pinch off spent blooms. When plants start looking too leggy or woody, they can be cut back by half.
Purple Trailing Lantana
For the healthiest, most natural looking lantana, perform hard rejuvenation cutbacks every spring.
One of the most favored and widely used types of lantana has always been and remains the solid lilac color and trailing growing habits of Lantana montevidensis, commonly known as purple trailing lantana.
Native to South America, these cascading plants thrive in Mediterranean climates around the world. They are year-round perennials in USDA zones 9 and above, and used as annuals in cooler climates. All lantana species, including purple trailing, are very sensitive to frosts and will not survive if precautions to protect them are not taken.
Plant 1- or 5-gallon size nursery specimens during the spring or fall when the temperatures are cooler so the cascading plants have time to establish before they must endure a summer or winter (spring is ideal, after the last frost). This lantana is sensitive to root disturbances so try to avoid them as much as possible when planting.
Give your lantana full, direct sunlight (6 or more hours per day). They will survive in partial to full shade, but will not have a healthy appearance. Keep moderately moist during their initial establishment period, after which time they only need occasional watering. An easy rule of thumb is simply to water just before the soil completely dries from the previous watering. Soil should be light and loose – heavy or sticky soil should be amended prior to planting.
For long-living lantana that look better year after year, allow your lantana to grow naturally during the growing season and perform hard rejuvenation cutbacks (cut down to three-inch sticks) every spring. When trimming, always use hand-held bypass pruners and never shear or shape with power trimmers.
Unlike common jasmine, primrose jasmine has a fragrance that is mild to indiscernible.
Jasminum mesnyi (or primrose jasmine) are a lesser known but equally beautiful species of jasmine native to Vietnam and parts of China. Now naturalized in parts of Mexico, Honduras, and the southern United States, these cascading plants easily and rapidly grow anywhere with similarly temperate conditions. This means slightly warmer, humid, and temperatures ranging from 60-degrees to no more than 80-degrees Fahrenheit.
Dark green foliage and a show stopping profusion of not white but bright yellow double blooms adorn long, arching branches that drape beautifully over rocks and walls. It should be noted that, compared to common jasmine, the fragrance of the primrose jasmine is mild to unnoticeable.
Immature nursery specimens should be planted in the fall in an area with plenty of sunlight. Planting holes should be about the same size as the nursery container. Space multiple plants about 6-feet apart to allow room to spread. While the new cascading plants are establishing water when the top 1-inch of soil has dried out, which should be around one time per week. Never water more than twice per week; overwatering must be avoided at all costs.
A bare minimum of two hours each day of direct sunlight is required for survival, and closer to six is far more ideal. These are sun-loving cascading plants, and full sun will result in an even more impressive bloom.
When it comes to soil, this type of jasmine requires three things: a neutral pH, sufficient drainage, and organic matter. A wide range of soil types can be tolerated if these requirements are met. If the soil does not have any or enough nutrients, it should be amended with a 3-inch top layer of compost.
The flowers and leaves of the coral fountain are toxic when ingested; watch children and pets at all times.
Russelia equisetiformis, as these cascading plants are scientifically known, are perfect for adding color to gardens in more extreme environments, such as high reflected heat and low water. They are hardy to USDA zones 9-11, and it should be noted these plants are particularly sensitive to low temperatures. It will not survive a frost and so must be protected at 55-degrees Fahrenheit and below. Though it can tolerate much hotter temperatures, it performs best in the 65-degrees to about 85-degrees range.
When planting, pick a location that gets plenty of sun; while coral fountain plants may survive living in shady conditions, they won’t flower as much or as brightly. Dig holes that are the same height as the root ball (or nursery container), and twice as wide. Loosen the root ball just a bit, place the plant in the hole, and spread the roots out. Pack soil lightly when backfilling, ensuring the top of the root ball is ground-level. Water in with a deep soaking immediately after planting.
Soil needs to have good drainage while still being able to retain some moisture, and should also be nutrient-rich. For the healthiest cascading plants, heavy clay or sand-heavy soils should be amended before planting. Add organic matter to the top 1-½ feet of soil; peat moss, compost, and dried shredded leaves are all great options. Once planted, try not to disturb the roots.
While establishing, keep the soil constantly moist without overwatering. Once mature and established, keep the cascading plants on a consistent, regular watering schedule throughout the growing season, allowing the soil to dry out between waterings.
Though selective hand pruning can be done to maintain the desired shape and remove dead growth, these cascading plants look best in their natural state. Spring cutbacks can be performed after the last frost of winter to keep it smaller and more compact.
Lady Banks’ Rose
There are many different varieties and cultivars of Rosa banksiae, with ‘Lutea’ (shown) being the most popular.
Rosa banksiae is one of the most widely used climbing plants used in gardening, as they are perfect for creating large privacy screens or covering unsightly areas. When left to its own devices, this extremely vigorous and thornless beauty easily fills in any space and has a natural cascading shape. It grows in the wild throughout parts of China and has been cultivated there for centuries.
Considering the native habitat, these cascading plants perform as evergreen in USDA zones 9-11. Full sun (6-8 hours per day) followed by some afternoon shade is an absolute must if the plant is to thrive and put forth the mildly sweet-smelling, buttery yellow double blooms for which it is known. It can survive in USDA zones 6-8 but the cooler temperatures force Lady Banks’ to act like a deciduous plant, causing it to drop leaves during the winter.
Plant immature nursery specimens in the chosen location in early spring after the last frost of winter. Spring is better, but these can also be planted in the fall provided it has at least 6 weeks in the ground until the first frost.
In terms of soil there is one thing these once-blooming cascading plants need, and that is good drainage. With that, and the full sun, virtually any type of soil is tolerated. Deep watering aimed at the base is needed for the first couple years after planting; do this a couple times per week, allowing the soil to dry between waterings. After a few years, drought tolerance is developed and spring rain or a once-per-week watering in extra arid conditions is all that is needed.
This beautiful groundcover is self-seeding and easy-rooting, making it ideal for rock gardens, hanging baskets, containers, and cascading over walls.
Trailing verbena – designated botanically first as Verbena canadensis and recently changed to Glandularia canadensis – is a colorful perennial favored for its low-growing, fast-spreading behavior and exceptionally long bloom period.
Also called rose verbena or rose vervain, these cascading plants are notably heat-tolerant, and as such perform best in USDA hardiness zones 5-11. They are grown as annuals in cooler climates.
As long as the soil is well-draining, whatever soil you have should work fine. Trailing verbena can tolerate some of the worst soil conditions as long as it’s not soggy.
In spring after the last frost, plant seedlings or nursery specimens in the warmest spot in your garden or yard (full sunlight needed if plants are to thrive). For the first few weeks, watering should occur when the top 1 inch of soil dries out. Once it is producing new growth, give it about 1 inch of water each week. Never allow the soil to become soggy.
Every month, feed with a water soluble fertilizer.
Nasturtiums come in a bush form as well, and both are edible.
Nasturtiums belong to the Tropaeolum genus, and the most beloved and widely used by gardeners is Tropaeolum majus, hailing from the Andes Mountains of Bolivia and Colombia. Other species like T. peregrinum and T. speciosum are also well known. Nasturtium leaves, seeds, and flowers are all edible.
They are best started from seed; any disturbance of their root system is risky and the process is quick and easy as seeds can be sown directly into the ground. If possible, choose a spot that gets full morning sun but is protected from the hottest midday summer heat. To prep the site prior to planting, simply loosen the soil by hand-turning.
In early spring, after the last frost of winter, drop seeds in the loosened soil about 10 inches apart, and lightly push down no more than ½ inch deep. Until germination, which should occur in about seven to ten days, keep the planting area evenly moist but not soggy.
Interestingly, these cascading plants tend to respond well to adverse conditions such as bad soil, very little water (especially fresh), and no fertilizing. The only care they really require is to have their area free of weeds to avoid competing, and deep, sustained waterings when the soil dries out, which could be up to a few times a week depending on your particular garden.
You can determine when to water by inserting your finger into the soil. If you feel any moisture below the surface at all, wait another day or two. If the soil feels completely dry, almost dusty, it’s time to water. To avoid mold, the cascading plants need to be dry by nightfall, so water early in the day.
‘Jewel’ is a perennial hybrid bred in New York and introduced to the world in 1985.
All strawberry plants belong to the genus Fragaria, native to Asia, Europe, and the United States. There are about 20 original species within the genus, and over 200 cultivars on top of that.
A popular and delicious option is the Fragaria ‘Jewel’, a perennial hybrid that is very low-growing with long, outstretched “runners” (called stolons) that spill over like other true cascading plants. Selective hand pruning can be performed on the stolons to shape the cascade as desired.
Ideal growing conditions for the June-bearing Jewel include 8-10 hours of sunlight per day and temperatures ranging from 65-75-degrees Fahrenheit. It performs best in USDA hardiness zones 4-8, though they can survive in zones 3-10 with the appropriate protective measures taken against cold and heat.
These strawberries also like well-draining, well-fed (via an application of compost at the beginning and end of every growing season) soil that is kept moist but not overly wet for the entirety of the growing season. Use mulch to retain moisture in the soil, cool off the roots, combat weeds, and, at the end of the season, to cover the plants to protect from frost. Lastly, keep the growing area free of weeds
Start from bare root plants or nursery specimens, as growing from seed is not an option with hybrids. Young specimens should be planted in the ground in April or May after a seven day hardening period (remember to keep the roots moist for the duration).
The color on bougainvillea are not flowers; they are modified leaf-like structures called bracts.
Not all bougainvillea can function as cascading plants; many have growing habits that are too upright, some are too compact, and others are way too big or aggressive to contain. But for gardeners who love bougainvillea, like me, there are some ground-hugging cultivars that are perfect for spilling over retaining walls: Oo-la-la, Purple Cascade, White Cascade, and Mrs. Butt are all cascading cultivars to try. I would personally recommend the Blueberry Ice, which features rare blue-violet bracts and variegated foliage.
Bougies perform best in temperate climates, with their ideal temperature somewhere between 60- and 80-degrees Fahrenheit. In USDA zones 9 and up it can live outside year-round. While they are hardy cascading plants, they do not like colder weather and are susceptible to frost damage. For the most profuse color display, choose a location that gets full sunlight for at least six hours a day. Bougies can survive in filtered shade but there will be far less color.
Soil should be well-draining and nutrient rich. Bougainvillea roots are incredibly temperamental, respond negatively to even the slightest disturbance, and are easily drowned by excess water, ultimately killing the entire plant. Amendments like perlite, sand, or vermiculite can be added to the soil to improve drainage.
To plant, dig holes that are the same depth as the root ball and treat with a high-phosphate fertilizer. Gently loosen the roots on your cascading plants, place into the hole, and tap the soil down around the base of the plant. While establishing, water enough to keep the soil damp but not flooded, after which water can be cut back to as needed only (when top three inches of soil have dried out). Fertilize in early spring and again in midsummer.
The majority of bougainvillea maintenance is in the pruning. They are fast, aggressive growers, though the cascading varieties typically grow at a much slower rate. In zones 9-11 the best time to prune is late winter or early spring, before a new growth cycle starts. Bougies bloom on new growth so they can actually be trimmed back after every growth cycle.
Rosemary is a member of the mint family, along with marjoram, oregano, basil, sage, and 3,500 other herbs.
Native to the Mediterranean Basin and Asia, this low-growing, evergreen herb has been introduced to every continent and is virtually maintenance-free once established. They are arguably the easiest cascading plants on this list to plant and grow.
The best time to plant creeping rosemary (Rosmarinus officinalis ‘Prostratus’) depends on elevation. High elevation zones should plant in the spring, and low-desert areas in the fall. Regardless of which category you fall into, always plant rosemary in locations with full sun.
To plant, prepare holes that are about as wide as and several inches deeper than the plant’s root ball. Add a soil/gravel mix to the bottom of the hole to improve drainage. Plant the rosemary (start with starter plants from a nursery), backfill the hole, and water in just to the point of wetting but not drowning. Continue to water everyday until it’s established, at which time you can cut the water back to once or twice per week. The level of drought tolerance they attain upon establishing is significant.
If there is good drainage, these cascading plants can handle almost any adverse soil situation, the exceptions being heavy clay and heavy moisture. Rosemary do not like wet feet and young plants will die as a result.
In the spring or summer, perform selective hand pruning to remove dead or damaged runners to keep the cascading plants balanced and healthy. Pruning also promotes new growth.
Sweet Potato Vine (Ornamental)
Notable cultivars for Ipomoea batatas include ‘Blackie’, ‘Marguerite’, ‘Tricolor’, ‘Sweetheart Red’, and ‘Sweet Caroline’.
Ipomoea batatas is the botanical name for the ornamental sweet potato vine, which is cultivated not for food but for their visual appeal and resulting merit in horticultural applications. Ornamental sweet potato vines are cultivars (subspecies) of the common sweet potato, and though edible like their parent plant, were not bred for consumption. And because both the food crop and the ornamental share the same taxonomic classification, the ornamentals are typically referred to by their cultivar designation to avoid confusion.
Though considered a perennial, this herbaceous, tropical, fast-growing sprawler is typically used as a summer annual. There are dozens of different cultivars available varying in size, color, leaf shape, and growing habits but there is one trait common to them all, and for which these cascading plants are known and loved: the incredible foliage.
Ornamental sweet potato is best suited to USDA hardiness zones 9-11. Purchase young starter plants from a local nursery and plant directly into the ground behind your wall. These are warm-weather, full-sun loving cascading plants that are sensitive to cold and frost, so outdoor planting should occur when temperatures are consistently 55-degrees Fahrenheit and above. Some initial training may be needed, which simply entails guiding the runners to and/or over your wall. After this, they should continue and cascade on their own.
The tubers from which these vines grow are highly susceptible to rotting from prolonged contact with water. As such, soil with good drainage is absolutely required for survival. Watering conservatively – just enough to keep the soil moderately moist – will help avoid issues with rotting. These cascading plants also respond well to soil with high organic matter.
Dead and dying (miscolored) stems and leaves can be removed at any time using clean snippers. Flowers on sweet potato vines are rare. The star of the show here is the foliage.
Coleus are thirsty plants and require frequent watering to look their best.
Once upon a time, Coleus was a somewhat forgettable shade-only plant. Depending on geographic location and climate, there were not many options from which to choose, if any at all.
That is no longer the case. Breeders have had a field day with Coleus and there are well over 1,000 different cultivars, all varying in size, growth habit, color, leaf pattern, and leaf shape. Some color and pattern combinations are exquisite to the point of looking unreal.
But perhaps more important than a bigger color palette are two other traits that some of these new cultivars have: full sun tolerance, and low-growing, trailing growth patterns. So, it is only somewhat recently that Coleus obtained the ability to function as cascading plants.
Coleus is a tropical perennial and cold hardy in USDA zones 10 and 11. In other zones it is used as a summer annual. They can take full shade to full sun and everything in between; that is cultivar specific, so be mindful of the cultivar you choose and its respective preferences. When the last frost of winter has come and gone, soil temperatures have increased, and nighttime temperatures stay above 60-degrees Fahrenheit on a consistent basis, then you know it’s time to plant young starter plants directly into the ground. They can also be started from seed.
Because the fast-growing Coleus has a fibrous root system, it is happiest in moist, well-draining soil. Organic matter should be turned into the soil before planting. A topdressing of mulch after planting provides another layer of insulation and keeps soil temperatures stable.
It should be noted that these are not drought-tolerant cascading plants. Coleus plants must be watered frequently to look their best, and the more sun exposure they have, the more water they will need. If you observe wilting, water right away; they will snap right back. The hottest days of summer often mean watering more than once per day.
Cultivars with trailing growing habits: ‘Burgundy Wedding Train’, ‘Yosemite’, ‘Road Trip’, and anything with “trailing” in the cultivar designation, i.e. ‘Trailing Queen’, ‘Trailing Rose’, or ‘Trailing Salamander’
Jen is a master gardener, interior designer and home improvement expert. She has completed many home improvement, decor and remodeling projects with her family over the past 10 years on their 4,500 sf Victorian house. She is also a passionate farmer who keeps goats, chickens, turkeys cows and pigs on her farm, and an instructor for her community’s Organic and Sustainable Farming project.