Pruning apple and pear trees can be a daunting prospect for the novice. For a start, not all cultivars produce and carry fruit in the same place on the branch. Depending on the variety some bear fruit on the tips, others on spurs. It isn’t necessary to have a detailed knowledge of the physiology of a fruit tree, but a few basic principles are useful. Understanding which buds will bear fruit and which will form leaves is a good first step.There are essentially two different types of bud on a fruit tree:
- Growth bud: a bud from which leaves or a shoot develop
- Fruit bud: a bud that flowers and then yields fruit
During the first year of growth, a new shoot produces embryonic buds, known as axillary buds, along the length of the shoot. These buds form at the base of a leaf – the leaf axil – hence, axillary buds. It’s much easier to see them once the leaves fall in the autumn.
Over the winter, axillary buds lie dormant. It is only in spring when growth hormones in the tree determine which buds will develop into a growth bud, fruit bud or remain dormant.Distinguishing between a growth bud and fruit bud is relatively easy from mid summer onwards. Growth buds are slim and pointed and lie close to the stem. They are usually much smaller than the fruit buds. Fruit buds become noticeably fatter than growth buds and often develop downy scales. In the third year the fruit bud extends to become a knobbly, stubby growth called a spur. These will keep bearing fruit each year and over time will develop into a spur system.
Once you are confident about distinguishing a fruit bud from a growth bud, the next step is understanding the fruiting habit of the apple tree that you are pruning. This will be the subject of the next blog.