With warmth and summer sun, I always enjoy transforming the area close to the back of my house into an exotic paradise filled with large foliage and vibrant coloured flowers – and aeoniums play a starring role in this. Their succulent, shiny leaves and burnished colours make an unusual addition to any garden for summer, whether mixed with other plants or potted singly as a feature on the patio.
My small collection of different types has been built up over many years, starting with the popular variety ‘Swartzkopf’, it’s almost black leaves making a strong statement, the colour intensifying with the strength of the sun. I’ve swapped cuttings of other varieties with friends over the years and bought a few young plants from nurseries. At its biggest, my collection numbered about 30. But having lost some and given up on a few weaker growing sorts, I’m now down to a more manageable half dozen that are my old friends and favourites.
Where do aeoniums come from
I’ve been lucky enough to travel to Canary Islands, Madeira and North Africa where aeoniums originate from. Keep your eyes peeled and you’ll see them growing on steep rocky slopes, in walls and atop roofs in their native climate. And as succulents they are superbly adapted to coping with heat, sun and free-draining soils.
But it often comes as a surprise to many that they are not desert plants. They do need a small, regular amount of water if they are to keep growing well. In drought conditions they have an ability to go semi-dormant, losing many of their leaves and retaining the merest tuft of succulent leaves at the top of their rubbery stems. In prolonged dry spells however, the plants can desiccate and die.
Generally though, the hot summers of their native environment are coupled with sporadic rain, and the Atlantic keeps winters very mild and moist for them to thrive in the winter.
How to look after aeoniums
Understanding the conditions that these plants are adapted to provides useful insight into how we need to care for them. They can’t cope with winter frost or winter wet – particularly in combination, so aeoniums need to be brought indoors in all but the mildest, frost-free places. They are well suited to a Mediterranean climate.
In places with frosty winters they are brought into a frost-free greenhouse, conservatory or indoors, usually between late September and late April. Gradually drying the compost in pots is also a good idea at then end of the growing season to slow down leaf development and toughen up tissues. This has the added advantage of reducing their vulnerability to rotting off. In this condition they will also be able to survive occasional temperatures down to zero celsius.
The key to success with aeoniums is to grow them in pots of free-draining compost. I use bagged cactus compost or John Innes (loam-based) seed and cuttings compost, mixed equal-parts by volume with horticultural grit is ideal. This will be create an open structure that will allow water to drain through and pull fresh air down through the compost as it does so.
They don’t require additional nutrients – particularly in the form of nitrogen which will promote soft, sappy growth. In this state, aeoniums are vulnerable to collapse under their own weight, fungal infections and cold weather.
Which are the best aeoniums to grow
There are lots of different varieties of aeonium, with foliage ranging in colour from green through bronze and purple to black. Some have variegated leaves with foliage edged and marked with cream, green and bronze. They also vary in stature from large, single-stemmed forms to branching multi-headed types as well as tiny, compact varieties.
My particular favourites are A. ‘Voodoo’, ‘Velour’ and ‘Cornish Tribute’. A good selection is available by mail order from Penberth Plants, Surreal Succulents and Corseside Nursery, all of whom stock other succulents.