How to grow Spiraea
A beautiful late spring /early summer flowering shrub, Spiraea is very hardy and suitable to grow in most locations, although for the showiest flowers Spiraea is best grown in full sun. Spiraea is very easy to grow and self sufficient and has no particular growing or pruning requirements, unless the shrub is getting too large, or tangled, when you can opt to do so a light trim after flowering. Spiraea is a genuinely low maintenance easy to grow shrub which really needs no attention at all once planted which means it is a green wheelbarrow shrub.
Once established Spiraea is easy to grow and all that is required is trimming or pruning if it gets too large after flowering in summer. If the shrub does need pruning, take out the old shoots from the base and trim back the younger stems to required size. If you do decide to prune Spiraea, it is best to prune after flowering in late summer
Spiraea is decidious and this means it looks very different in the winter compared to summer, as shown in the image below which is Spiraea canescens left in early summer, right in winter. It looks dead in the winter, so if you come across it in the garden, don't be tempted to dig it up, come the spring it will reward you. Spiraea are fully hardy H6 which is to -10 down to -20.
Recommended varieties of Spiraea to grow
There are several Spiraea which have the RHS award of garden merit which is always a good indicator when picking a shrub.
Spiraea Japonica 'Anthony Waterer' left has lovely pale red flowers, compact and upright it grows up to 1m and is fully hardy, illustrated in the first image top left.
Spriaea Canescens has arching stems, grows up to 2.5m with lovely white flowers is a popular species regularly sold in garden centres, easy to grow looks well in any border especially in a woodland setting although flowering best in sun.
Spiraea × arguta 'Bridal Wreath' is a popular variety with, as the name suggested, lovely white flowers carried on arching branches growing up to 1.5-2.5m
Spiraea Nipponica 'Snowmound' 3rd image right has arching habit as well with masses of white flowers and grows up to 2m. One of the most attractive varieties for the garden because of the profusion of flowers.
A Spiraea with really bright golden foliage is Spiraea japonica 'Golden Princess' which has pink flowers and a more compact variety growing between .5 -1m ideal for smaller gardens.
Spiraea in Summer and Winter