the brief flowering of a true aristocrat

The Paeonia rockii is flowering.  This is a beautiful and exotic tree peony that is one of the most fabulous things I have ever succeeded in growing.  The flowers, which only last for a few days, are huge, 15cm or more across, single, white, and have at the base of each petal a purple blotch.  They have a sweet scent if you stick your nose in, though they don't broadcast their fragrance around the garden.  The leaves are divided, a cool grey-green, and the whole plant exudes elegance and glamour.

It is not easy to find, and not cheap when you do find it, the reason being that it is difficult to propagate.  We have only ever had them in stock at work once in the eight years I've been there, which is when I bought mine.  That was in 2005, and we were charging £30 for them then.  It was only a single twig about 30cm high, which I planted next to a large stake, not so much to support it as to highlight its position and make sure I didn't tread on it.  The following spring it produced one flower, so out of proportion to the still diminutive shrub that I cut it off and put it in water, for fear that its weight would snap the top off the plant.  I was very pleased to see that the initial flower was a good one, as some strains in cultivation are better than others.  By now it is a well-branched shrub around 1.5m in all directions.

My plant grows in a west facing bed with shrub roses to the south of it, so it is sheltered from the worst of the wind, but definitely in less than full sun.  Tree peonies come into leaf remarkably early in the spring, and the books advise avoiding an east facing aspect lest the morning sun fall on the frozen leaves.  The spot where Paeonia rockii is has reasonable drainage, and although conditions are probably a bit drier than it would like in an ideal world, it has done better than the other varieties of tree peony I've tried, which have been in places where the clay rises to the surface.  They can make a lot of growth in a season, but can give a lot of it back the following winter through dieback.  I have never observed any pest or disease on them.  Talking to customers at work I get the impression that one of the main hazards to tree peonies is jobbing gardeners treating them in the same way as herbaceous peonies and cutting them to the ground.  You don't want to do that.  Just take any dead bits out once the plant has started into growth.  The stems are brittle and can be bowed right down by the weight of the flowers, seeming too frail to support them, so a bit of staking is sometimes called for.