Indubitably witches’ broom, not two trees
I came across this fine example of witches’ broom in a roadside tree planting of Prunus Awanui. That particular flowering cherry is known to be vulnerable to witches’ broom. It is the green section coming into dense leaf earlier than the rest of the tree and without flowers. Left to its own devices, over time the witches’ broom will take over the tree and you will no longer see much in the way of spring flowering. If you leave it for a few seasons, it also becomes harder to remove the affected sections without destroying the shape and structure of the tree.
Basically, witches’ broom is a mutation within the tree – possibly similar to an immune disorder in humans – which causes dense, twiggy growth in that section. It does not appear to heal itself and it does not grow out of it the following year. There are multiple causes but no general treatment beyond surgery – removal of all affected parts of the plant. Cherry trees are particularly prone to it, although you won’t find them in the campanulatas or Taiwanese cherries. Generally it is seen in the Japanese cherries and the hybrids. If you spot it now, mark it because it is harder to identify later in the summer when all the branches are in leaf. Spray on paint is handy for this, or a tie. Pruning cherry trees in high summer is recommended to reduce disease getting in.
On the bright side, witches’ broom mutations are what have given us many of the dwarf conifers so they are not all bad.
First published in the Waikato Times and reprinted here with their permission.
1. The freestanding horizontal espalier. You can see clearly the advantages of a two dimensional plant. Good air movement will reduce disease. It is easy to tend the plant and the fruit all receives equal sunlight. You can also see that the supports are heavy duty. This is not an exercise to be done with a few bamboo stakes and stockinette ties.
2. The cube requires some heavy duty framing but is quite stylish, even if I was worried by the top branch that was trained back on itself. Using a frame which gently rusts as it ages will make it less visually intrusive than the tanalised pine we often favour in this country. It is the plant shape you want to emphasise, not the support structure. This design allows good air movement through the centre of the tree.
3.The diamond row was visually the strongest in terms of pattern. I raised my eyebrows at the potential rubbing of bark where branches cross. Stem damage can let disease into the plant and a rule of thumb in all gardening is to avoid crossed branches. Presumably in an intensively maintained espalier, you are replacing the branches regularly with fresh growth so there is a bit of leeway if this is the look you want.
4. There is little doubt that your fan-shaped espalier will look better if you clad the fibrolite garage in old brick veneer and casually pose a stylish, vintage, terracotta forcing pot in front. The advantage of espaliering against a wall is the increase in heat for marginal crops. We don’t need to do it for apples and pears in this climate but I can see that it could work well for figs and some of the stone fruit.
5. I have mentioned trendy stepovers before – the training of an espaliered fruit at knee level. This is a dry climate technique and where rains are light and misty. Our torrential downpours will cause rain splash and spread disease faster than you can blink. We need maximum air movement and to be above the splash line in our humid climate. That said, you can see disease in this example. I have yet to see one which remains at step-over height all growing season.
6. These table and chairs are obviously not yet established. I offer them as an idea without comment, secure in the knowledge that regular readers will know exactly what my personal opinion is likely to be. However, for those who like a little novelty in their garden, here be they. I even recorded some instructions for you.
Tikorangi The Jury Garden 