Hydrangeas, clematis, roses and rhododendrons are the stars of the garden and tend to sell on sight. Even if you came into Nags Hall for a box of fertiliser, if you walk past a display of hydrangeas in bloom it is difficult to resist buying one!
But spare a thought for spiraeas, easy shrubs that are too often neglected and are supporting plants in the garden, providing colour in various ways and are much better for wildlife than vibrant hydrangeas. Spiraeas can be divided into two main groups, the white-flowered spring shrubs and the generally pink-flowered summer types based on Spiraea japonica.
The latter are all low and twiggy, generally growing no more than 1m high and wide; many are much smaller. They all flower in summer on the new shoots so you can prune them in spring to tidy them up. If you prune them quite hard, shearing them off at 15cm, growth will be vigorous, which is good in the forms with coloured foliage. Flowering will be a bit delayed but you will get lots of flowers later in summer. Or you can lightly prune out some older stems if you don’t like the idea of chopping down your plants completely.
These spiraeas are all easy to please and they will grow in sun or part shade in any soil provided it is not waterlogged. I have planted lots in my new garden, which has pretty awful soil, because they grow quickly and are reliable and the bees love them. Their long flowering season makes them good for pollinators. Butterflies seem to visit from time to time but it is bumblebees that seem to like them most but I think they are foraging for pollen rather than nectar because they scamper around the flat or domed heads of blooms.
Their size and twiggy habit makes them perfect for mixed borders with herbaceous plants and bedding or at the edge of paths. Although the flowers are usually shades of pink, the foliage can be green, flushed purple when young, yellow or bright orange.
‘Goldflame’ is the most common of all and it has gorgeous young foliage. In spring the whole plant is covered in burnt orange leaves. As the season progresses the leaves turn greener but the young leaves are always coloured. In summer the deep pink flowers appear and I am never sure if I think they make an attractive combination. But they are showy and the bees like them. I prefer to give the plants are hard prune in spring which delays flowering and encourages the best foliage colour.
‘Shironana’ is a cute oddity. The green-leaved plants can produce pink flowers or white flowers and often both on the same stem. The plants are easy to grow and they flower throughout summer and every cluster of blooms is a surprise. I planted a short row of 5 plants along a path.
The flowers of ‘Pink Ice’ are simply white which is just as well because this is another that is grown for foliage. The new leaves are mottled with white and pink on red stems and they age to green and white. It is a neat, pretty plant and colourful all summer, though, like all these spiraeas, they loose their leaves in winter.
‘Sparkling Champagne’ is a new, British-bred spiraea with two-tone pink flowers in gently domed heads. It was named because the breeder thought the flowers looked like the surface of a glass of sparkling pink champagne. I have only had this a year and it is growing well and is distinctly different to the others and well worth planting. Like all the others, this will grow in a large patio pot but use John Innes No 3 compost when planting.
There are lots of spiraeas and many have coloured leaves but the latest I have added to my garden is ‘Neon Flash’. The foliage is flushed purple when young and the flowers are a good, bright pink though not quite neon – which is probably a good thing!
Most spiraeas will bloom throughout summer but it will keep plants tidy and promote more flowers if you trim off the old flowerhead which will turn brown.