Quick Guide to Winter Pruning of Pome & Stone Fruit Trees
Posted by Phytopath on Jul 26, 2011
Why are stone and pome fruit trees pruned in winter? Because we can easily see the structure and shape of the tree.
This makes it easier to decide which branches to remove or shorten, and which ones to leave alone.
It is not necessary to prune in winter.
You could prune your fruit trees after harvesting the fruit in summer and autumn, but the canopy of leaves may obscure your view. This may result in branches being missed that are possibly diseased.
It has also been noted by some commercial fruit tree growers, that early pruning can produce vigorous upright growth in some trees, while later pruning (late winter) appears to suppress the surge of vigorous branches.
I think you should always consider the local weather conditions before making a decision.
Some trees have strong apical dominance. Meaning the main trunk grows like a flag pole, reaching
for the sky. This is also called a central leader.
These trees should be cut back when young if you want to develop an open vase shape tree.
If you choose to constantly prune the central leader, control of apical dominance will be lost due to the number of new shoots competing for the new leader position. An increase in pruning cuts will then be required next pruning season and control of the subsequent regrowth will be lost.
They include: Apples, cherries, pears, quince, European plums and prunes.
I must include additional information at this point.
Some rootstock will have an effect on the overall shape and growth of the tree, sometimes reducing the overall height, as in the case of dwarfing rootstock.
Other trees do not have strong apical dominance and develop a more rounded shape.
Examples of these trees are: Apricot, peach, nectarine and Japanese plum.
Whatever fruit tree you are growing, it is a good idea to perform selective fruit bud removal when the bud density is too high, in an attempt to prevent alternate cropping.
One of the most important things you need to know before you make your first pruning cut is, where does the tree carry its fruit? Is it on new wood, old wood or permanent spurs?
Once you are familiar with the fruiting habits of your tree, you can then assess each individual tree in your care.
There are many different ways to prune fruit trees. Just ask a dozen different people and you will get a dozen different answers.
The most important question you should ask yourself is: why am I pruning this tree?
If the tree does not need pruning, then don’t prune it. But always look for any dead wood in the tree. Remove this first. Then look for any branches that are crossing over. This is an area for potential disease entry, so look at it, then choose one of the branches and remove it.
If you are pruning the tree to encourage fruit production remember that the tree needs its fair share of leaves as well. Photosynthesis produces sugars for the developing fruit. So do not sacrifice too many leafy branches.
Peaches and nectarines produce fruit on last season’s laterals so when pruning make the cut at a triple bud. Last season’s fruiting laterals should be cut back to the basal leaf buds.
Apricots. I personally do not believe in pruning apricot trees. If you never prune them, growth appears to be slowed down but once you start to prune an apricot tree, you’re then bound to continue pruning because of the vigorous regrowth.
Japanese plums produce flower buds on last season’s laterals and short spurs on older wood. Prune to shorten the older laterals and thin out the spurs.
European plum trees develop permanent spurs on two year old laterals. Prune long laterals to half their length.
Pruning apple trees can be a complex exercise because different varieties have different fruiting habits. Some trees bear mostly on laterals (Jonathan apples) so shorten these by about half their length.
Other apple varieties produce fruit on spurs (Granny Smith). Thin out congested spurs and shorten or remove strong laterals. Keep the shorter laterals for future spur development.
Pear trees are pruned similar to apple trees. Thin out old spur clusters, cut back strong laterals and keep the short ones.
Always sterilise your pruning equipment and make sure your implements are sharp.
If you are not sure how to prune your fruit trees, there are many good books available with step-by-step diagrams.
Botanical Names
Posted by Phytopath on Jul 4, 2011
To most people, botanical names are considered useless.
“They are too hard to pronounce and too long”, I have heard people say.
So why do we use them?
Because they are universal.
Imagine travelling overseas to a foreign country. A place where English is not commonly spoken and you do not speak the native language. Communication would be difficult.
But if you arranged to meet a botanist or horticulturist and mentioned a few botanical names of plants growing in that region, I am sure that after a few nodding heads you would be taken to the nearest location of those plants that were mentioned.
Now imagine a similar scenario but this time common plant names were used instead of botanical ones.
“I would like to buy some violets” you say. Which are edible (Viola sp.), “to make a violet syrup.” The person you are speaking to nods their head and takes you to a nursery selling African violets. What a disappointment, and they are not even closely related.
What if you had never actually seen the plant you were seeking? The common name that you are using could be a completely different plant in another country or even another state of the same country you live in.
What if the plant with the same common name was poisonous or a skin irritant?
You could find yourself in trouble, health wise, if you intended to ingest it.
So that seems a pretty good reason to use botanical names, especially if you are out of town.
An example of confusing common names exists here in Australia.
We have a tree called a ‘blue gum’, trouble is, there are three different Australian states that have a tree called
‘blue gum’ and they are all different species.
So not to confuse anybody, botanical names are the way to go.
When writing botanical names (correctly), there are just a few things to remember.
The Family name starts with a capital letter e.g. Myrtaceae
The Genus or generic name starts with a capital letter and is underlined or written in italics e.g. Eucalyptus
The species name is written in lower case and also placed in italics or underlined e.g. leucoxylon
Most people use only the genus and species when referring to a particular plant, so an apple tree would be written as Malus domestica
There are other ‘categories’ of plants, like variety, cultivars and hybrids, but let’s start with the basics. 
