All About Peonies
Peonies produce some of the most glorious flowers amongst the large and varied world of perennials. The big, often blousey blooms come in a range of colours from white to yellow, pinks of all shades and orange to deepest red. Once established they need very little maintenance and are very long-lived. Place them in a border with other perennials and the peony provide beautiful flowers from May to late June, depending on the variety. That is not the only gift the peony brings to a garden, in spring the new shoots of fresh leaves are a beautiful tone of rich purple-red, and later as the leaves change for a short time to fabulous autumn shades.
Peony 'Adolphe Rousseau' (Lactflora) P. 'Eliza Lundy' (Hybrid), P. 'Hillary' (Intersectional), P. 'Anglet' (Tree)
Types Of Peony
Herbaceous peonies start to loose their leaves around the end of summer, eventually nothing will be showing above ground in winter. They are divided into two distinct groups. Peonies in the largest group, Lactiflora and Hybrid peonies.
Lactiflora peonies are the largest group of peonies, these are the ones most commonly found in garden centres. Thy have large, opulent flowers that bloom from early to late June in colours ranging from white to cerise pink, dark crimson and, in more recent years, yellow. There are no true ‘fire-engine’ reds.
Hybrid peonies are the other type of herbaceous peony and are the result of crossing species peonies. Unlike Lactiflora peonies, which all have similar mid-green leaves, the foliage of Hybrid peonies vary from shiny to dull green, and the leaf shape from round-ended to deeply divided. Their flower colour is also different and can range from white and pale- to very bright pink, shades of apricot or true red. Many also bloom earlier than Lactiflora types, from late April onwards.
Intersectional peonies, a relatively new group, were created by hybridising herbaceous with tree (woody) peonies. The leafy stems emerge each spring from the base of the plant and by autumn some have turned woody, while others die back just like herbaceous peonies. The flowers are very large, usually single or semi-double and range from white, apricot and lilac-pink to true red and yellow. In addition, the petals of some start out one colour then gradually change in tone as the bloom matures. Intersectional peonies are grown in the same way as herbaceous peonies and bloom at similar times to Lactiflora and Hybrid peonies.
Tree peonies should be more accurately called ‘woody’ peonies because their form is not a tree but a shrub, with woody stems that remain over winter. The flowers and leaves are usually much bigger than herbaceous peonies, although they bloom at the same time. They are organised into three horticultural groups: Japanese, Chinese and Lutea Hybrids, each creating a different shrubby shape.
How To Plant A Bare Root Peony
Nothing could be easier, provided a few rules are followed.
- Simply dig a hole wide enough and deep enough to accommodate the roots. Place the plant in the hole following the planting rules below, and cover with soil.
- Unless a period of dry weather is forecast, they don’t need watering.
The roots of Herbaceous Lactiflora peony, Intersectional peony, Tree peony, Hybrid peony raised from peony species
Herbaceous peonies (Lactiflora & Hybrid) need to be planted with the eyes no more than 5cm below the soil surface. If they are planted too deeply the plant may struggle to produce flowers.
Intersectional peonies are planted in a similar way to herbaceous peonies. Ignore the level of the woody stems and using the red eyes on the wide crown as your guide to depth, plant these around 5cm below the soil.
Tree peonies are planted in a totally different way to herbaceous peonies, especially if the plant has been grafted. On a grafted plant, the lower section of root will be thicker than the upper, which is the graft. The point where the two sections meet should be at least 8cm below the soil surface, which might mean that very little of the ‘stick’ is visible. Seed-raised peonies, such as Paeonia delavayi, are quite happy planted as deep as you wish.
Autumn & Spring Tidy Up
Herbaceous peonies can suffer from fungal diseases, and spores persist in the soil over winter. Once the plant is looking tatty, the leaves and the old flower stems should be cut down and removed. I generally do this in spring when the new shoots start to show. Here in mid-Wales, that can be as early as late February.
Autumn leaves on herbaceous lactiflora peony, Intersectional peony 'Callie's Memory', trimmed stems of Paeonia delavayii, metal ring support used on P. 'Coral Charm'
Intersectional peonies are generally disease free, but to keep a plant looking tidy you can always remove leaves when they drop in autumn. I also prune the woody stems before the leaves start to emerge in spring so the clump looks neat and domed, rather than an unbalanced mix of a few tall and many shorter stems.
Tree peonies retain some or all of their leaves and will provide winter shelter for birds and small creatures. If you wish to tidy up the plant in autumn, this can be done by simply snapping the leaves off the plant. However, the old foliage is much easier to pull off in spring when the new leaf shoots start to grow. Spring is also the time to tame a plant that has lost its shape or grown too big. Use secateurs to prune the woody stem just above a red leaf bud. Take out the amount of stem you need to create a neat shrub, but not so much that the pruned stem is left with no leaf buds. Removing one or two stems entirely won’t harm the plant.
Fertilising
I rarely fertilise my peonies but if you do, never use fresh farmyard manure. If this sits too near to the peony stems it will cause them to rot. Make sure you use organic, very well-rotted manure and apply in a ring at least 15 cm from the plant and before the new shoots appear. Alternatively, apply a general-purpose granular fertiliser according to the instructions.
Summer Support
Some peonies need support to keep the flower stems from tumbling over. The sturdiest and most elegant are made of metal, but a ring of thick stakes can look attractive when secured at the top with a circle of intertwined willow stems. Supports should be put in place before the flower stems become too tall.
Watch Claire on 'Gardener's World 2022 Winter Special'. If you don't want to watch the whole peice, fast forward to 11 minutes into the show!
