Divide and conquer
Gardening guru Peter Cundall advises how to achieve bloomin’ marvellous results with peonies
THERE are about 30 known peony species and countless cultivated varieties many bred from the East Asian species Paeonia lactiflora.
These form the largest group of herbaceous peonies which are treated as border perennials.
Growing a metre high during spring and summer, they completely die down in winter.
The other, far smaller peony group includes the much sought-after and far more expensive “tree” peonies. Many old varieties can grow 4m in height and when in flower are considered to be among the most astonishingly beautiful of all ornamental plants.
All peonies are popular because of spectacular flower displays and superb foliage.
Tasmania is ideal for growing these wonderful plants which need cold winter soils and relatively cool summers.
Peonies have substantial roots, most
All peonies are popular because of spectacular flower displays and superb foliage
being large and swollen, like huge dark brown carrot clusters. So perfect drainage is essential. Although tolerant of most soils, peonies prefer enriched loams, even with a little clay, with an annual dressing of dolomite limestone.
Tree peonies (Paeonia suffruticosa and hybrids) are relatively expensive to buy, mainly because they are hard to propagate from seed or cuttings. Some people have successfully divided plants or even taken layers but the most common form of propagation is by grafting on to herbaceous peony rootstock. The plants are then planted deeply into the soil so the top-graft eventually forms and survives on its own roots.
Seeds may be as large as peas and are notoriously difficult to germinate, although the yellow-flowered P. lutea is a little easier. However, if seeds are sown while still sticky-ripe in late summer they
often succeed. Seedlings send out roots only during the first growing season, making it difficult to tell if germination has occurred. Only during the second year will shoots appear above the soil. Dry, mature seed immediately lock into hard dormancy and are extremely difficult to germinate without special treatment.
Tree peonies prefer part shade, allowing flowers and foliage shelter from afternoon sun. The beautiful leaves emerge during spring, with some showing rich, coppery tints that continue into flowering. Flower buds are large and the massive, heavy flowers — always needing supports — may be yellow, red, purple,
pink or white and almost every shade between.
Herbaceous peonies cost less to buy and the plants are at home in full sun. Lack of light is a common reason why they may fail to flower. Like tree peonies they are best left undisturbed with some outstanding clumps of herbaceous peonies being than a hundred years old and thriving.
All herbaceous peonies die back to the ground in late autumn so make sure locations are clearly marked. Clumps may be lifted and divided for extra plants from April to late July but keep in mind the fleshy roots are easily snapped.
When clumps are lifted, the dull-white growth buds can be seen at the top of each root mass. Cut clumps apart so each division has one or two healthy buds. These buds should finish up just below the surface after divisions are planted.
Peonies are now available at garden centres and specialist suppliers. To obtain the best selection, study specialist mail order catalogues.
When your parcel of brown, uninteresting divisions arrive, don’t be put off by the appearance because they will develop into some of your most precious garden delights. You will have to wait a couple of seasons for your new peonies to start flowering but you’re in for a lifetime of spring glory. And every year those spectacular displays of magnificent flowers gets bigger and better.