20 of the Best Container Shrubs
All gardeners enjoy the delightful task of potting up spring containers or stretching our summer and spring colour displays by changing out fresh combinations. For the most part, this is small pot gardening. But, one of the most valuable ways in which to use containers is to see them as part of the landscape rather than as isolated decorative items. This is especially useful when planting into the ground is not an option, for it encourages us to plant them up with trees and shrubs as permanent fixtures. Long-time reader, Clive, set us on the path in search of shrubs and trees for patio containers, and, after filtering out many species, we found a list that covered a few essential pointers for successful containment.
Where to use them:
Place them to filter the wind
Provide privacy around the patio
A row of shrubs in containers can create a wall or boundary.
Group an evergreen with other containers of flowers or foliage, or group several of those evergreens together to create a corner or define a space.
Their air cooling and cleaning impact are greater too than would be a few small, low-growing arrangements.
Not all plants will grow well in containers; shrubs often stay smaller in a pot than their ground-grown counterparts, though this depends on the plant, climate, and container.
Can establish roots in a limited amount of soil.
Easy to prune – look to multi-stemmed species
Have moderate water needs; place those in need of frequent watering close to the house.
Choosing your container:
Plan to re-pot them every other year, allowing for a gradual increase in pot size to accommodate root growth. Repot sooner if you notice roots escaping from the drainage holes.
Avoid planting into a narrow-necked pot as it is difficult to get a plant out once its roots have spread.
A tall, narrow pot is less stable than a squat, low one.
Plant tall, narrow plants in wide-based or heavy containers to prevent them being blown over.
Drainage is critical; add extra holes to ensure good drainage.
Never reuse a pot without sanitising it first.
Healthy plants should be transplanted from nursery pots to containers that are a few inches wider and deeper.
For a plant, life in a container is much different than one in the ground, and, while containers hold the growing medium and provide necessary drainage, the plants depend on you for ongoing water and nutrients. Keep a space of around 3 cm between the soil and the container rim for watering.
Put some quality potting soil in your container. Garden soil is unsuitable as it doesn’t drain well in containers and could be more prone to weeds, insects and diseases. For shrubs, use a soil based potting mix rather than a soil-free mix because it is heavier and will help anchor a bigger plant and its root system. It also helps provide a sturdier base for the container in the wind.
Feeding: Contained shrubs need monthly feeding with a balanced fertiliser during the growing seasons of spring and summer. Keep plants well mulched, and top up regularly.
Watering: a couple of times a week in summer, especially on hot, windy days when they will dry out faster.
Shaping: Pruning not only shapes the plant it also helps limit or slow down root growth which is important for container plants. Keep trimming away long branches. Use a slanted cut just above an outward facing node. Cut off any dead or dying stems or branches or growth that spoils the shape; keeping only the strongest and straightest lets the plant use its energy for healthy growth and flowers.
Our list is by no means exhaustive but does give you a wide choice from which to choose.
Allophylus species: Allophylus dregeanus: The Forest False Currant is an evergreen shrub or small tree up to 5 – 6 m, with a straight stem and attractive glossy dark green leaves. Sprays of sweetly scented flowers appear from February to May and red fleshy fruits from March to September. This forest species requires compost rich soils and frequent watering. A. natalensis has a dense crown, sturdy stem and is multi-stemmed. Tiny white to cream flowers in scented clusters from March to July. Both species attract birds. Makes a good screen and windbreak, is water wise and slow-growing.
Dracaena aletriformis: Large-leaved Dragon Tree. Grows 3 – 4 m in the ground. Has large, shiny and leathery leaves that can grow to 1 m long. Usually single-stemmed. Produces large sprays of creamy- green flowers followed by bright orange seeds. Makes a great container plant in rich potting soil. Tender to frost and requires moderate watering.
Mackaya bella: The Forest Bell Bush has dense, lush foliage and should grow between 1 and 2 m in a pot. This shrub requires water to thrive, and ensure it is placed in full shade. Produces large white to lilac bell-shaped flowers from spring to summer. Prune after flowering.
Mitriostigma axillare: The Dwarf-loquat has beautiful glossy foliage that makes it a worthwhile container shrub. It has a compact growth habit, is slow-growing and full size is anything between 50 cm and 3 m. It should remain small and neat in a container. Strongly scented cream to yellow flowers cover the plant from August to November, followed by bright orange fruits. Sensitive to frost, but will survive in a warm corner on the patio. Relatively pest free.
Peddiea africana: Poison-olive (or Green-fingered Tree), is an unusual shrub or small tree that grows to 5 m but takes readily to containments. Flowers are pale lime-green, tinged purple-pink inland, growing in clusters at branch tips from September to April. These are sweetly scented at night. All parts are said to be poisonous, so be careful.
Psychotria capensis: The Black Bird-berry is another shade-loving plant with glorious foliage and compact growth that makes for an excellent container specimen. This evergreens shrub reaches 3 to 7 m in the ground, but small when contained. Golden yellow flowers form large heads from August to January followed by large clusters of shiny yellow fruits that ripen to red and black. Lovely decorative plant. Frost tender and water wise.
Rhamnus prinoides: The Glossy Blink-blaar has a more wayward growth habit than the species above, but is easy to control. Foliage is outstanding, glossy, bright green with serrated margins. Summer flowers are tiny but fruits, though small, are most attractive and speckle the foliage like Christmas holly. Grows 4 – 6 m, is frost hardy and water wise and can form dense hedges. Takes well to pruning. Will take some sun.
Xylotheca kraussiana: The African Dog-rose is a beauty and is one of the best choices for a patio container with compact growth, dense foliage and lovely large white flowers with egg-yellow centres that cover the shrub from spring through summer. These are sweetly scented. Multi-stemmed, it grows between 2 – 5 m and takes pruning if necessary. Will take morning sun. Protect from frost.
Coddia rudis: The Small Bone-apple makes the most delightful container plant with multiple stiff, arching branches grow initially upwards and outwards before curving back down again. Leaves are tiny, mid- to dark green, with slightly wavy margins. They grow in clusters along the stem. From August to March, pale yellow funnel-shaped flowers grow from leaf axils.
Coleonema species: The Confetti bushes have an upright growth and reasonably dense foliage growing off a single stem with branches from low down making them suitable as a screen or windbreak. They also take coastal conditions, a boon for gardeners needing protection on the patio. Small star-shaped pink or white flowers cover the tiny needle-like leaves in masses. Shrubs grow 1 – 2 m. They tolerate a mild frost and are water wise but need regular watering after planting.
Crassula ovata: Pink Joy copes with salt air, frost, drought and sun. Glossy foliage is most attractive even when not covered by white to pink flowers in winter and summer. This is a sturdy, compact and rounded shrub, a perfect choice as a screen and windbreak. Full container size should be around 1,5 m.
Diospyros whyteana: The Bladder-nut has exceptional foliage; glossy bright to dark green that looks outstanding year round. Multi-stemmed with a lovely neat shape; foliage is usually dense and low-growing, but it is easy to prune if needed. Will take sun and partial shade. A large shrub but slow-growing, it is water wise and frost hardy. Good choice for coastal gardens.
Hoslundia opposita: The Orange Bird-berry is a little-known shrub but is an excellent container specimen. Part of the mint family, leaves are fragrant and pale green, and the flowers and fruits produce a simultaneous show or orange and lime green from October to February. It forms a rather soft, sprawling shape up to 1,2 m high, multi-branched and simple to trim to shape. It is a hardy shrub, though possibly only moderately frost hardy, and is water wise. A beautiful shrub.
Karomia speciosa: The Wild Parasol Flower has a slim profile, perfect for squeezing into a corner, or line a narrow patio to provide a privacy screen. Place containers in sun, light or partial shade. Shrubs can be single or multi-stemmed and produce a profusion of purple and pink flowers in summer and autumn. It can be deciduous in colder climates. Plants grow 3 – 4 m tall, but they take well to pruning, so trim to a suitable height. Plants cope with moderate frost and do require frequent watering.
Ochna serrulata: The Mickey-mouse Bush is a charming container shrub growing slowly to 2 m or so in sun or partial shade. It has beautiful yellow flowers in spring, followed by the ‘Mickey-mouse’ black and red seeds. Young spring foliage is tinged a pink-bronze, maturing to a glossy bright green. Plants are water wise but prefer regular watering. Can be pruned lightly after fruiting to keep it dense and in shape.
Portulacaria afra: The Spekboom should grow in every garden as a carbon absorber and general air cleaner, invaluable for life on the patio! This succulent is grown around the world as a bonsai and container subject. Form is dense and upright, and shrubs are easy to prune to shape. Drainage is critical! It is easy to nip off a few leaves and pop them into the salad to add a tasty if somewhat astringent flavour.
Rothmannia globosa: The September Bells is a beauty with sweetly scented white to cream flowers in September. Flowering is for a brief period anytime from August to November, but displays are so beautiful that one can bear the plain green foliage for the rest of the year. Form is slender and height up to 6 m. Plants tolerate a moderate frost and are water wise.
Senecio barbertonicus: The Succulent Bush Senecio form a compact, rounded shape with upright, bright green needle-shaped leaves and acid yellow flowers from winter to summer. Plants prefer sun but do well in partial to dappled shade. Plants are moderately hardy and water wise; water often after planting, then only when the soil is dry. The Senecio makes an excellent screen and windbreak, and a lovely foil for small pots of bright colour.
Turraea obtusifolia: The Small Honeysuckle-Tree forms a neat shrub in sun, but has a rather scrambling form in shade or semi-shade. Plants grow up to 3 m high, but the multi-stems take well to light pruning to keep in shape. Pure white flowers cluster among the glossy dark green leaves in summer. Plants will also take some shade and need water and food in summer.