Tree Hygiene

Our plot has many old trees: damsons, apple, plums and greengages.  This is my old Codling Apple Tree.  Despite suffering from several common diseases, the tree is healthy.  Don't be discouraged as there is much you can do to minimise or eradicate these diseases.

Can you see the green Codling Moth pheromone trap? That is designed to catch the moths whose larvae leave holes in the apples. I have a similar one for the plums. You can also spray them with insecticide: Deltamethryn. See RHS Codling Moth Chemical Control for details.  As the pests overwinter in bark and leaves, rake them up and dispose of them, but do not add them to your compost heap or you will encourage them more!


Black Spot or Scab is caused by an air-born fungus and black spots appear on leaves and fruit.  The fruit is often edible but looks unsightly.  Tree hygiene can be effective.  Raking up leaves and burning them can stop it spreading. You can spray the trees with fungicide (Myclobutanil) if you prefer. See Apple Scab in Jim Conrad's Newsletter, for more information.


Bitter Pit or Bitter Rot also appears as brown blotches on apples and leaves (see below).  This is caused by calcium deficiency.  Tree hygiene and mulching around the base of the tree will help. See the BBC's Gardening Advice and What are these spots on my apples? to find out more about Bitter Pit and Glomerella Leaf Blotch and how to fight it. The RHS  also have a good piece on caring for your tree and Controlling Bitter Pit, here.

Canker requires similar attention: cutting out diseased and dead wood  or split and withered branches can help to slow its progress. Raking and disposing of infected leaves is another way to limit the spread of the disease.  Die Back can also be a sign of Canker.  This picture below is the effect of canker on my plum tree. I cut the branch off and burnt it.


This large branch (below) on my Codling tree, is also showing signs of Canker. Cracked branches like this sometimes ooze a gummy substance.  This branch has healed over with time and seems to have resisted the disease better than the young branch above. You can improve the soil PH and follow tree hygiene to improve the tree, but there is no chemical control for Canker.

Brown Rot turns fruit mouldy on the tree and is caused by a fungus.  It enjoys damp conditions. There is no effective fungicide for Brown Rot.  Fruits like these withered plums (below) should be removed and burnt, along with any twigs and leaves affected by the brown rot.  Tree hygiene prevents over-wintering the fungus spores, so rake up those leaves and light that bonfire!


Last year, I planted new trees on the plot.  I did my research and purchased disease resistant trees (Bramley 20 and Honey Crisp).  They are pretty hardy, but suffered with Black Spot in their first year.  They showed no sign of disease when I bought them so I felt demoralised for a moment... and then went on the attack.

Vigilance and good tree hygiene worked. This year, my trees were better established and stronger.  I watered and mulched them and they have been much healthier.  Here is my first crop of Honey Crisp apples, all ready for picking... Don't they look fabulous?


Thank you for reading this post! 
Have you any orchard moments to share with us? Please comment below.

Not spotted your fruit tree problem? Maybe one of these sites can help you:

Identify Fruit Tree Pests and Diseases
RHS Apple Tree Problems, Questions, Answers and Problem Gallery
Jim Conrad's Naturalist Newsletter Apple Scab
Bitter Pit and Glomerella Leaf Blotch What are these spots on my apples?
RHS Apple Canker and how to control it
Home Guides SFGate.com Fruit Tree Diseases Where Branches Die
RHS Fungicide for Home Gardeners
Check apple varieties at OrangePippin Trees for their disease resistance.

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