Blue is not the commonest of shades in our gardens but at this time of year it is easy to have a surfeit of this divine colour. These statuesque plants can be found in colours ranging from the purest of whites through pale to dark blue and almost black – just thinking of these fabulous plants gives me goose bumps! They can be ludicrously tall or very small, so there is no excuse not to have some of these sublime plants in the summer garden!
Agapanthus – common name ‘African lily’ and ‘Lily of the Nile’, though I’m not sure why it has the latter common name as the species are indigenous to South Africa not Egypt! For those of you who have never grown Agapanthus, they produce strap-like leaves that can be evergreen or deciduous producing flower stalks topped by an umbel of flower containing anything from 10-30 or more blooms that are tubular and mostly having swept back petals. Thankfully Agapanthus are generally pest and disease free – just the sort of garden-worthy plants I like to grow!
Agapanthus are considered invasive species in places like New Zealand and Madera, but our cooler climate keeps them from spreading into the wild though quite a few are very hardy surviving our resent cold winters well in the ground. I have recently rebuilt my collection of Agapanthus back up after losing most of my containerised ones to the hard winter a few years ago hence they are now all brought into frost free conditions for the coldest months of the year.
The forms that are deciduous – usually with thin leaves, tend to be the hardiest in general with Headbourne hybrids being some of the most well-known here in the UK, but thanks to breeders around the world there are now dozens if not hundreds of cultivars available for our delectation, especially if you go to nurseries that specialize in Agapanthus though in saying that several well-known local Norfolk garden centres now stock a good range and Taverham garden Centre here in Norwich has at least fifteen in a good range of sizes, otherwise a search on Google will find plenty to wet your appetite!
Agapanthus in general prefer well drained gritty soil in a full sun position where they enjoy being baked in high summer. They will take dappled shade well though they tend to produce more foliage and fewer flowers. Although these extreme beauties of the garden take drought in their stride they never-the-less appreciate moist soil when in bud and flower. They also produce the best blooms when overcrowded as they seem to enjoy having a restricted root run; hence they make excellent container plants. Many of the large leaved forms prefer being grown in containers as they are less hardy and can easily be moved into frost free conditions for the colder winter months kept on the dry side just giving them enough water so they don’t go dust dry, though many of mine refused to go completely dormant last winter as it was so darn mild!
There is always a tendency for gardeners to re-pot too often which makes them produce more foliage than flowers. I like to see a potful bulging at the seams as this does produce a prolific number of flowering stems. Eventually they do have to be divided which may reduce the number of flowers the following year until they become re-established.
Agapanthus praecox is one of the most common types available; with long strap-like leaves up to 50cm (20ins) or longer with flowering stalks up to 1.2m (4ft) tall. The flowers can be light or dark blue and tend to be very large. A. praecox ‘Albus’ has huge globes of tightly packed, snowy white, trumpet-shaped flowers which rise above the broad, evergreen, strap-like leaves in July and August. There is nothing like walking through the garden at dusk and seeing the lowering sun shining though their enormous heads which can be up to 30cm (1ft) across where they literally glow like jewels!
I have one labelled as Agapanthus umbellatus ovatus that I just had to purchase a few weeks ago as it had a fasciated stem (three stems fused together) which is now topped with one absolutely enormous head containing well over 200 individual flowers (I gave up counting!)
‘Phantom’ is a beauty – its strap-shaped leaves are retained in all but the coldest winters, making this a great choice for year round interest. From late summer, it turns from merely interesting into something fabulous, when clusters of trumpet-shaped flowers appear on top of elegant 1m (3ft) stems. Each white bloom looks as though it has been infused with the softest shade of lilac-blue.
I have become rather fond of the darker forms and one I particularly like is ‘Northern Star’, which has dark purple buds opening into star shaped blooms that are blue with darker purple stripes down each petal. ‘Graskop’ is an inapertus cultivar hailing from the town of Graskop in South Africa. It has a compact head of drooping, dark violet blue flowers from late July into August, which emerge from almost black buds – it’s absolutely fabulous and a must for lovers of dark flowers! Not quite so dark but equally delectable is ‘Indigo Dreams’, a deciduous variety producing an abundance of eye catching deep indigo blue flowers. Right now!
There are a few small variegated foliage forms like Agapanthus ‘Silver Moon’ which has narrow leaves that are green with creamy-white edges that in high summer produce narrow 45cm (18ins) spikes of mid-blue flowers, or how about the even more diminutive Agapanthus ‘Tinkerbell’, an attractive little plant with light green and white striped leaves topped with pale blue flowers in summer.
There are many more I could mention here but alas I have run out of space to tempt you with these glorious high summer bloomers, so why not pop along the to the Exotic Garden this weekend and see for yourself how alluringly captivating they really are – you won’t be disappointed!