We are indebted to Angela Simpson and Jeff Rose for providing this article.
There are various aspects to consider before unleashing your secateurs and pruning saws on your treasured fruit trees. So, here are some tips that our volunteers learned on the course, with a particular focus on apples and pears.
The aim of fruit tree pruning is to achieve a balance of cropping and growth in a tree. You want to achieve a combination of young fruit bud, good size fruit and a structure that will support a good yield. Unpruned apple trees left to their own devices produce smaller fruit, are more susceptible to disease and start to fruit biennially – a natural way to deal with pest and disease (less fruit, less infection). Excessive growth results in less fruit and little growth results in excessive fruit, and so on, so the right pruning keeps the tree healthy and in balance.
WINTER PRUNING (from Leaf fall to end of March) results in more growth and less fruit.
SUMMER PRUNING (from End July to mid-August) results in more fruit bud formation and less growth.
If the FORM of your tree is ‘rigid’, i.e. Cordon, espalier, or fan shaped: winter prune until the tree fills the area you want, then Summer prune with the occasional winter ‘thinning out’. Trees with ‘flexible’ forms, i.e. ‘Open centre’ and ‘centre leader’ trees are usually larger and pruning can be more flexible but complicated. The aim should be to allow good light penetration thus providing a higher fruiting yield and allow the branches to droop.
Fruit buds are round and plump, from which appear the flowers and, when pollinated, the fruit. A growth or wood bud is slender and born in a leaf axil, much smaller than a fruit bud, and gives rise only to leaves, never flowers. A healthy tree has both fruit buds and growth buds, but if you cut off all fruit buds there is no fruit.
‘Spur-bearing’ trees make up the largest group of apples e.g. Cox’s Orange Pippin, Sunset, Egremont Russet, James Grieve. They are compact and produce short, branched shoots – or spurs – with pointy fruit buds, mostly on two-year-old wood. A neglected tree can become congested with spurs and produce a lot of very small fruit. There are some ‘Partial Tip-bearers’ such as Bramley’s seedling, Discovery, Worcester Pearmain, which produce fruit both on the tips of young laterals and on spurs. A few are tip-bearing only – fruit buds are found at the tip of long shoots produced the previous year, so don’t prune the tips!
The size of a mature Apple tree depends as much on its rootstock as the variety. Most of those with Dwarfing or Very dwarfing rootstocks grow quickly upwards in early years but slow and nearly stop when full cropping starts. They need staking and support throughout life. The M27 rootstocks bear smaller fruit and crop earlier. They start producing fruit after 3 years and have 10 years commercial life. If the tree grows up the centre as it grows older and you don’t remove, this will dominate the tree and the apples will only grow at the top and edges, not the centre.
It is important to consider the age of the tree and also the age of the branch. The number of rings that protrude around a branch will tell you the number of years growth
The wood of a branch will consist of young wood, fruiting wood and grey wood. If the branch is not growing, do not prune.
PRUNING A PEAR OR COX in the field…
At Brogdale, John Easton showed us how to prune in a A-shaped form, controlling growth of shoots so that the tree is wider at the bottom than the top. First remove any dead, diseased or damaged matter. It may be necessary to cut back to core stem. Start pruning at the top. Cut the top right back to the trunk but keep one leader on top (can be small), in a different direction each year. Trim branches to the stem – don’t cut half the branch unless you want to make it stronger. Cut off downward facing shoots or if the branch is 5 years old or more (check the rings). The aim is to have upward facing branches in a goblet shape. Count the fruit buds – up to 50 fruit buds is ideal. With younger trees, you can remove up to one-third of leading branches/shoots.
PRUNING A MATURE BRAMLEY
John showed us a magnificent mature Bramley tree, a lower inner branch of which had a number of new shoots growing.
His guiding principle is:
- Cut off 1/3rd to stem (particularly downward facing).
- Trim to 1/3rd length / 1/3rd of producing fruit buds
- For the remaining 1/3rd bend over flexible longer shoots and tie under main branch.
Keep the centre of the tree relatively open to allow light to centre.
Thin the branches by removing inward-facing and crossing branches.
HOT TIPS
RHS.org.uk is a great guide on the properties of your tree and how to care for it. Type into the ‘Search’ the name of your apple or pear tree.
Bacterial Canker: – don’t put infected wood or leaf in compost or a woodpile – Destroy it.
PEAR RUST can occur (possibly because there are Juniper trees nearby). Pick all the leaves off and destroy. If the rust is still occurring after 7-8 years, there is no solution!
FRUIT THINNING – APPLES AND PEARS: – Before the June/July Drop, you can thin the crop by cutting just below the fruit (do not pick the fruit off). There are usually odd numbers in a bunch – 3 or 5. The centre fruit is the KING fruit (usually the largest) which does not store well so can be cut off. If there are five fruit in a bunch, cut off the King fruit and two more, leaving two on the tree.
CHERRY TREES and PLUM TREES: – Prune only between May and August (as that is when spores of bacterial canker appear). Don’t prune the suckers of Cherry trees in winter – chop off with a spade when the sap is growing in Spring.
KEEP TRACK OF PRUNING: – Record: date, tree variety, rootstock, age, bearer type, form, location; date of pruning, level of pruning, thinning, tying down, canker removal. Also, keep a record indoors of the information on the label of the tree, as the label will deteriorate outside. Take a photo of the tree, before and after.
BUYING A TREE: – Don’t buy a tree that does not have a rootstock designation. If it is on vigorous rootstock, you will need to cut back. Use dwarfing rootstock for orchards.