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Flamboyant peony roses

  02/07/2013 at 12:43 pm

The peony rose has been cultivated by the Chinese for over three thousand years, so you could say they are the leading experts at growing their favourite flower. The true national flower of China is the plum blossom which was officially designed in 1964, but to many, the peony rose is the unofficial national flower of china, as chosen by a national survey in 1974. Before I go any further, I must clarify that peony roses are not related to roses, except in the similarity of their showy flowers, that is where the similarities end.The next big confusion with peonies is that many people do not realise that there are two very distinct types of peonies. To keep it simple, peonies are classified as tree peonies or herbaceous perennials, and within each group they are then classified by either their flowers or growth habit.

Tree peonies as the name would suggest is where they grow into trees, well nor quite as this will depend on the individual variety. Tree peonies grow between 1.2 - 3m (4-10ft) but as usual this varies according to individual species and most important the soil conditions. As I write my own tree peonies are taking a hammering from the high winds and sudden down pours. As you can guess this plays havoc on their huge flowers, which can be reach between 15-30cm (6-12in). Do not let this put you off, as they are truly magnificent flowers, even if for a fleeting visit. They require sun for three to four hours a day, any longer than that and the flowers tend to fade. I planted mine in a south facing border, but planted them in the foreground of Himalayan birches, thus giving them shelter from midday sun. They like a rich deep soil that is free draining and will be short lived in wet soils. Talking of longevity , my tree peonies are over ten years old. By tree peony standard this makes them little more than seedlings. A tree peony between twenty and thirty years old is considered a young plant, which is based on their life expectancy of between fifty and eighty years.

Tree peonies are not difficult to look after provided you follow a few simple rules. Tree peonies are draught tolerant once established, but young plants must be watered during dry weather. Remove seed heads after flowering to stop plant wasting vital energy in making seeds.

Herbaceous peony roses may not be as flamboyant as their family relatives (tree peonies) but they can certainly give them a run for their money. Many people often wonder what is meant by the term Herbaceous, this is simply a botanical term used to describe a plant, by which their leaves and stems die down to the ground at the end of the growing season. Peonies are often referred to as herbaceous perennials. This is used to describe any herbaceous plant that regrows every year. The big plus with herbaceous peonies is that you do not have to to worry about winter damaging leaves and stems. I always mulch mine in autumn with leaves, which has the added benefit of providing organic matter, and most importantly insulates the roots from frost damage.

I am regularly asked why peony roses are not flowering, the usual answer is to give them more time. Unlike many other herbaceous plants that are planted in the autumn and give you an abundance of blooms in the first summer, peonies do not follow this rule. I have only two words of advice when planting peony roses, time and patience. I remember when I moved my twenty year old peony Bowl of Beauty. Well I guess it took the best part of seven years for it to return to its former glory. Peonies are often described as sulky plants as they do not like to be moved, well I do not know about sulky, but undeniably they do not like to be disturbed.

The ideal growing conditions for herbaceous peonies are a sheltered site and this is self explanatory when you see their huge blooms which are susceptible to wing damage. They like a slightly alkaline soil with a ph of between 7-7.5 with plenty of organic matter. For all those that are fortunate to have acid soil, you will have to add dolomite lime to increase the ph. As a rule herbaceous peonies do not require any flower support, but heavy rain will lodge flowers that are in full bloom. By the way, peonies make fantastic cut flowers and will easily last up to a week. If you are cutting for flower arrangement, cut them in tight bud and watch their beauty unfold when brought into the house. Here are three of my favourites: Paeonia lactiflora Bowl of Beauty , Paeonia lactiflora Sarah Bernhard and Paeonia lactiflora Duchesse de Nemours.


Do do list:

1. Water, water and more water. Tip: It is vital that newly planted shrubs and trees are checked regularly for water. I am always amazed at just how many people forget to water plants according to the weather conditions. The last couple of weeks have been very windy, which has played havoc on shrubs and trees. Make sure you cover bare soil with bark mulch to retain vital moisture.

2. May is the month that I say, full steam ahead. Tip: Now that the soil is warm you can plant many crops direct into the soil from seed. Beans, carrots, peas, lettuce scallions and many more. Depending on the weather conditions, plant every two weeks to quarantee succession cropping.

3. Plant out summer bedding plants now. Tip: do not give your summer bedding plants a sudden shock. If you have purchased bedding plants from your local garden centre, they will have been hardened-off in a cool glasshouse before sale. For anyone that has grown their own from seed or plugs, you must aclimatise them to out-door conditions. Put them out during the day and bring them back in at night to harden-off.

By Eamonn Wall