Insights into tree husbandry

I have been through the wars. My right foot had become increasingly painful, until I could no longer put any weight on it. One of my arches had collapsed slightly, causing a tendon to become inflamed. It was agony. One of my few remaining indulgences has been to retain private health insurance, so I hot-footed it off to a specialist, who immediately put the offending pedal extremity into plaster. But why had this happened? I put it to the footsie guru that it could have been caused by a lifetime of digging, using the arch of my foot to exert pressure on to the top of spade and fork. He confirmed that this could well be the cause, a kind of repetitive strain injury over the years, so from now on I must remember to use my heel.

One of the most charming people I have ever met is Colin Crosbie, who is in charge of woody plants at RHS Wisley. There is nothing he doesn’t know about tree husbandry. Years ago, he made me all too aware of the long-term dangers of trees with a ‘forked’ main trunk, that is to say a ‘double’ trunk in the shape of a Churchillian victory sign.

What happens, and I have witnessed the sad demise of many a statuesque beech for this reason, is that as the tree grows and the shelf in the fork widens, damp detritus accumulates. The result is a rotting of the wood at that juncture, as water begins to seep down into the dead wood at the centre of the trunk. Such a weakened branch can suddenly break off, even on the stillest day in summer. These forks are widespread; indeed, I saw one on a blue cedar the other day, and it is not uncommon to see such misshapen young trees for sale in garden centres.

The art is to cut out one of the forks, choosing the straightest or strongest, making sure that you do not cut too close to the remaining one. By ‘too close’, I mean that a 1in stump should be left on a smaller tree. However ungainly it might look at first, this forlorn stump will eventually disappear over the years, and you can go to sleep at night with the comforting thought that you have prolonged the life of a long-living tree, to the tune of a generation or two.

In my last garden, I allowed common valerian (Centranthus ruber) red, pink and white to self-seed among smartly clipped box balls contained within terracotta pots: the contrast between the lax and the disciplined worked very well. As a result, I now have a thriving population of seedlings of these welcome perennials around the bases of each box plant, meaning that I have more than enough for my new garden. It is also a reminder of the tenacity of this plant, and the importance of dead-heading it before it has a chance to pro-liferate its kind all over the shop. I am going to plant them in patches of poor ground (which they will love), but they will all have to be taken out of their present pots before they start to send their strong roots down too far.

In the footsteps of the mildest January on record, all those gardeners who have included winter-flowering plants in their landscape have been rewarded handsomely. The winter flowering cherry, Prunus x subhirtella Autumnalis, which normally looks its best in spring, has over-excelled itself, and Japanese quince was fully out in January.

The pretty pink flowers of Viburnum x bodnantense Charles Lamont have never looked better: a trip to RHS Hyde Hall in Essex a few years ago taught me that Charles is a preferred alternative to the ubiquitously planted Dawn, because his flowers are not only larger, but also more tolerant of the endless cold and wet of winter.