Peter Dowdall: When I think of agapanthus, I think of summer
Agapanthus likes hot, dry days filled with sunshine and thrives in warm conditions and free-draining soils. Picture: iStock
During midsummer, our gardens are all alive and vibrant with so many colours, scents and wildlife.
Agapanthus, commonly known as Lily of the Nile, stands out for me as one of those plants which are synonymous with summer in the garden. When I think of agapanthus blooms, I think of hot, dry days filled with sunshine and this is most likely because they like warm, sunny conditions and free-draining soils in which to thrive.
This perennial plant, native to South Africa, derives its name from the Greek words "agape", meaning love, and "anthos", meaning flower.
The plant was first discovered by the botanist and physician Dr James Edward Smith, during an expedition to the Cape of Good Hope in the late 18th century.
Since then, agapanthus has become extremely popular for its showy blooms which are freely produced once a plant has become established. The root system needs to become congested for the plant to flower, which is why they are ideally suited to growing in pots as the gallop of their roots is restricted.
When planting from a pot into the ground, you can expect that it may be a few years before the plant flowers again as the roots, which have sudden access to a whole new world of soil, will take a while to clump up once more and start blooming.
Agapanthus plants are known for their clumps of strap-shaped, glossy green leaves that range from 30 to 100 centimetres in length. These leaves provide an attractive backdrop to the plant's main attraction—the stunning blooms.
Agapanthus flowers are borne on tall, sturdy stalks, and their colours vary from shades of blue and purple to pure white. Each inflorescence consists of numerous trumpet-shaped blossoms.
The foliage of some varieties is evergreen, whereas with others they are herbaceous and all the foliage dies back underground each winter and then, just to confuse us more, some of them are what is termed as semi-evergreen, meaning that they will die back some years and not others, depending on the severity of the winter.
Don’t let what happens to the foliage concern you, however, for it is the blooms for which they are grown.
There are several popular agapanthus varieties available to gardeners, each offering its unique charm. The 'Blue Umbrella' cultivar is celebrated for its vivid blue flowers and compact habit, making it ideal for smaller gardens. 'Albus' is a white-flowered variety that exudes elegance and purity.
For those seeking a dramatic display, the 'Black Pantha' cultivar presents deep purple blooms that create a striking contrast against the green foliage.
This year sees a new introduction in the world of agapanthus as the variety Black Jack has won the Plant of the Year at the RHS Chelsea Flower Show in 2023.
As it's new, I have yet to grow it and thus cannot speak with any experience.
However, I have seen it in full bloom and it is quite something, according to Patrick Fairweather from Hampshire’s Fairweather Nursery who has trialled Black Jack for five years,
“Black Jack has a wonderful, statuesque form. It’s sturdy and upright, with strong stems and lush, slightly arching evergreen leaves. Perfect for terraces, balconies and small gardens, it’s a low-maintenance plant that demands little water and will survive a few weeks' summer holiday with no water. It’s climate-proof, tolerating high summer heat and high winter rainfall.
"Black Jack thrives in peat-free composts and is perfect for pots, but needs some protection from hard frosts. It’s a magnet for pollinators, and having grown Black Jack for five years, I can say without a doubt that it sets a new benchmark for dark-flowered agapanthus... Irresistible.”
Agapanthus plants are tough and resilient and thrive in a variety of growing conditions. They prefer full sun but can tolerate partial shade. Well-drained soil is essential to prevent root rot, as agapanthus dislike overly wet conditions. When planting, ensure the crown of the plant is level with, or just above, the soil surface.
Feeding agapanthus once or twice during the summer months with a good quality organic seaweed feed will help to promote flowering. Deadheading spent flowers will promote further blooming and stop the plant’s energy from going into seed production.
Though you can grow them, quite easily from seed, by far the best and quickest way to bulk up on numbers is to propagate agapanthus by division during the winter. Dividing the plant every three to five years will help to rejuvenate the original plant and of course lead to lots of babies which can be planted throughout the garden or, which will make you a very welcome guest in other gardens.
Got a gardening question for Peter Dowdall? Email gardenquestions@examiner.ie
