Candyfloss hydrangeas sweeten summer's end
Published 21/08/2011 | 05:00
THE hydrangea most commonly seen in gardens is the mop-head type, pink or red on limy soils and blue or purplish on acidic soil. While these are very beautiful, and a good choice, there are some other hydrangeas flowering now which bring their own special magic.
Unlike the common mop-head, which has a rounded, bun-shaped cluster of flowers, these others have a much larger, taller and more pointed flower head, roughly the size and shape of a candyfloss on a stick, starting pale green and turning creamy white and later taking on a pink tinge.
The shape of the flower head gives the species its botanical name. The tall pointed shape is known in botanical terms as a 'panicle' and the species is Hydrangea paniculata, the 'hydrangea with panicles'. This is a bigger grower than the mop-head type, capable of reaching three metres tall in good soil and about as much across.
As a big plant, it is ideal for large gardens and big borders, decked out with dozens of frothy candyfloss flowers. It is deciduous and has good autumn colour in shades of yellow. When the leaves are off, it is quite a light-stemmed open bush, not at all heavy in appearance.
While it can be allowed to grow as a large bush, it is easy to keep to a smaller size. It can be pruned hard each spring, cutting it to about 30cm. If well fed with compost, it quickly produces new stems that can grow out to 90cm in a few months and most of the new stems carry a large flower. Ordinary mop-head hydran-geas flower mostly on the previous year's growth, while the panicle hydrangea flowers on the current year's growth.
Flowering on the current year's growth delays flowering until late summer and early autumn, and even more so when hard-pruned. But this is an advantage because the best show takes place later. Like all hydrangeas, the flowers are long-lived, lasting well into the autumn, becoming suffused with a touch of raspberry pink and sometimes green.
There are several named varieties. 'Floribunda' is a popular one with plenty of large flowers. 'Grandiflora' has large flowers, sometimes 40cm long, often arching over. 'Kyushu' is a short form but the flowers are not great. 'Praecox' is an early flowering kind, but that is no great advantage.
'Tardiva' is late-flowering, upright in habit, but the flowers are a bit light. 'Limelight' is good, white with a greenish touch. 'Pink Diamond' and 'Pinky Winky' have a touch of pink, and 'Vanille Fraise', meaning vanilla strawberry, is a beautiful confection. Most of these are difficult to get, except 'Grandiflora'.