The name agapanthus is derived from the Greek words agape which means love and anthos flower. So these truly South African plants (they’re endemic to southern Africa) could be called love flowers. They have many different common names including African Lily, Blue African Lily and Lily of the Nile. Whichever name you choose for these easy to grow and rewarding plants it’s appropriate to say that every gardener simply loves agapanthus.
Today they are cultivated extensively around the globe having been introduced into Europe in the 1680s. Some 10 different species are found growing in the wild and they have all contributed to the array of garden hybrids that abound today.
Agapanthus are described as perennial herbs with thickened basal stems and fleshy roots. The leaves emerge in pairs from the basal stem. They’re strap shaped, glossy and slightly fleshy. All grow into clumps of multiple stems and increase in size continuously. Some hybrids sport variegated foliage that adds an extra dimension to their overall appeal. Flowers are borne on tall scapes (flower spikes) that are held high above the foliage. Tubular flowers are arranged in umbels. Blue is the dominant colour with white forms also proliferating. Plant breeders are trying their level best to develop a whole new array of spectacular agapanthus blooms. The fruit’s of their labour is already beginning to show outstanding results.
Agapanthuses are now available in a bewildering array of hybrids. These are definitely superior in formal plantings in terms of flower colour and uniformity. The species types tend to be highly variable in height, colour and flowering time, but they’re still very showy in more informal settings.
Cultivation of and garden uses for Agapanthus
There are many different sized agapanthus from extra dwarf types with leaves hardly 20 cm long to huge plants with flower spikes almost 2 metres tall. Selecting the best plant for your express purpose is half the success of growing these free flowering plants. Some types are deciduous and die back to ground level in winter. These are not cultivated as extensively as their evergreen relatives. They perform best in full sun, well drained soils and respond to annual feeding and mulching. Agapanthus are able to withstand extended periods of dry weather and bounce back from cold winter frost damage. Gardeners often plant them in shade and end up being disappointed when they don’t produce flowers.
Growing agapanthus in a pot
Agapanthus grow well in pots especially young plants that like to have their roots restricted and may only need repotting into a bigger pot after 2 years. Plant your aggies in potting soil with added compost for extra drainage and nutrients and place in a sunny position. Water your pots a couple of times a week in hot weather, and feed once a week with a liquid plant fertiliser. If you live in a very cold area, bring pots under cover during autumn, or use frost protection fabric to cover and protect from the very cold spells.
Agapanthus Pests and diseases
Although agapanthus are relatively pest and disease free they are prone to attack by lily borer during the spring and summer months. These are caterpillars (moth larvae) that eat the base of the leaves and bore into the stem causing the plants to go mushy and collapse. Treat the problem at first detection with a registered insecticide (cypermethrin is registered for this) or resort to a regular preventative application to circumvent infestation. Lily borer can be devastating and appears to be getting worse. Healthy, well fed plants are less likely to be affected.
Rust is a fungal disease that causes brown spots on the leaves. The leaves can become yellow and drop off. Treat with a copper-based fungicide.
Caring for agapanthus
Agapanthus should be left in one place for a number of years until overcrowding makes thinning out necessary. Many clump-forming perennial plants reach a point where they have to be dug up from the garden and split in order to thin them out. If left to grow unchecked for season after season they become extremely thick, untidy and start losing condition owing to overcrowding. It’s advisable to replant them every second or third year and autumn is an ideal time to carry out the task.
In order for them to re-establish themselves before winter, the evergreen species should be transplanted just after flowering in late summer, but the deciduous types should be divided or transplanted in early spring.
Keep agapanthus plants happy by planting them in full sun or light shade, watering regularly (but don’t overdo it), and feeding them with a slow-release fertiliser in spring.
Some of our favourites
- Agapanthus praecox subsp. orientalis ‘Blue Velvet’
- Agapanthus ‘Buccaneer’
- Agapanthus africanus ‘Lapis Lazuli’
- Agapanthus orientalis ‘Queen Mum’
- Agapanthus africanus ‘Summer Gold’
- Agapanthus africanus ‘Peter Pan’
- Agapanthus africanus ‘Double Diamond’
- Agapanthus ‘White Ice’
- Agapanthus ‘Blue Ice’
- Agapanthus ‘Black Pantha’
- Agapanthus ‘Amethyst’
Dividing clump-forming perennials
Many clump-forming perennial plants reach a point where they have to be dug up from the garden and split in order to thin them out. If left to grow unchecked for season after season they become extremely thick, untidy and start losing condition owing to overcrowding. It’s advisable to replant them every second or third year and autumn is an ideal time to carry out the task.
What you need
A garden fork; bucket of water; secateurs; compost; bonemeal; a metal rake; a garden spade and water.
What to do
Lift mature clumps from the garden using a garden fork. Remove all the dead or damaged foliage.
Wash the soil off the roots in a bucket of water or under the hosepipe. Carefully pull the plants apart using a sharp knife or a pair of secateurs. Cut down the foliage to between a third and a half of the normal length. This reduces transpiration and decreases transplant shock. Trim the roots as well.
Prepare the soil for replanting by turning it over then adding compost and bonemeal. Dig this in well and rake. Plant the splits at the same growing level as before. Space the plants evenly with sufficient room between them to allow for future development.
Once the area is planted, water thoroughly to settle the plants in. Continue watering at weekly intervals until the plants are established.
Plants to divide by this method
Agapanthus in various forms and sizes, Neomarica species, Dietes species, Hemerocallis hybrids, Clivia species and hybrids and Liriope muscari in different forms.