trouble with Pileostegia

The Pileostegia viburnoides on the front wall of the house is coming into bloom.  I say on the front wall, but most of what is blooming is at ground level and making a break for it towards the drive. It has had a chequered history, mostly my fault and not the plant's.

You may not have heard of Pileostegia.  I hadn't, until I saw some at the plant centre where I used to work.  Then I saw a large and very fine specimen growing on a wall at Bodnant (or at least, I am pretty sure it was at Bodnant.  It was part of an Edwardian scheme with steps, terraces, and a vast wooden latticework pergola painted a fetching shade of duck egg green, that must have cost an absolute fortune each time it needed renovating).

Hillier's manual of trees and shrubs has kind things to say about Pileostegia viburnoides.  One of the best climbers for any aspect including shady walls, it says.  The first meeting Mr H G Hillier had with this plant was in 1922 in Orleans when the leading French nurseryman of the time, Mons Chenault, proudly pointed to a plant covering the front of his house.  I did not want it to cover the front of mine, but I had a reasonable sized blank wall, east facing, and thought it would look very fine with a Pileostegia.

Several years later I can report that the house front is in no danger of being covered.  My first specimen quietly died, despite my watering it from time to time.  The second plant did better, reaching to the first floor and making some width, before I allowed it to be overwhelmed by tentacles of Boston ivy that had grown all the way round from the back.  That is literally half the way round a reasonably sized detached house. but the invasive habits of Parthenocissus tricuspidata are another story.  I thought the Pileostegia did not mind sharing its air space with the Boston ivy, but I was wrong.  It resented the shade cast by the ivy's big leaves tremendously, dropped most of its leaves, and the smaller twigs died back.

The Systems Administrator chopped the Parthenocissus back from the end wall and front of the house when painting the wooden cladding, and swore it must not be allowed to return since on its first foray it had lifted the sill of the dining room window and allowed damp to come in.  It has grown back this summer, and one of my jobs for this autumn is to limit its spread once again to the trellis under the veranda.  Friends who admired the view from the dining room through the fringe of lobed leaves hanging across the top of the window exclaimed how pretty it was, and commented how lovely it would look when the leaves turned red in autumn.  They were right, it would look very pretty, but it is a wrecker.  Now the birds have finished nesting it has got to go.

So what's so good about the Pileostegia, given its tendency to die and inability to compete? Pileostegia viburnoides is an evergreen, self clinging climber, related to hydrangeas.  Self clinging is useful if you want to grow a climber up a brick wall that won't need painting, and don't fancy having to bash nails or vine eyes into the brickwork to fix supports for your climber.  There are not so many evergreen climbers around, or self clingers that won't try to take over the entire building, or climbers that are happy with an east facing aspect.  The leaves are long and leathery, an agreeable shade of mid green if the plant is happy, or a sad, chlorotic shade of pale green if it's not.  Asking a hydrangea relative to grow on meagre sand was probably a big ask, and my plant has appeared unhappy at regular intervals, quite apart from the catastrophe with the ivy.  Nowadays I water it fairly often when I'm watering the pots around the front garden, and sprinkle fish, blood and bone around its roots several times a season, and that has cheered it up.

I managed to divert a couple of the ground level shoots that were trying to escape from the ivy so that they grew back towards the house, and they are now obediently ascending the wall.  They are not flowering this year, which is fine, since I don't want them to flower, I want them to focus on growing, but the remains of the older parts of the plant are flowering.  The flowers are held in big, flattish plates, which remain for a long time in bud, each bud a tight little white ball.  The balls open to reveal a cluster of protruding stamens surrounding a minute central female part, while there are no visible petals at all.  The whole effect is very dainty, with a pleasing contrast between the dots of the unopened buds and the froth of the open flowers.  It is not scented, but the bees love it.

The climbing hydrangeas are slow to get going as a group, so some of my difficulties with Pileostegia may be due to the nature of the beast as well as my own failings.  I think I have read somewhere that it's best to regard recently planted ones as honorary container plants, and feed and water accordingly.  If I haven't read it somewhere else then you read it here first.  Now that our relationship is on a better footing I am looking forward to a solid bank of evergreen leaves, and large, lacy white flowers in summer, enlivened with foraging bees.