A tragedy: The leaves turn yellow, dry out and fall off. The flowers have withered, a rich harvest is a long way off. The sweet cherry that radiates vitality can quickly turn into a sick misery. In most cases, fungi are the culprit.
What diseases occur in sweet cherries and how can they be prevented?
Common diseases of sweet cherries include shotgun disease, spray blotch and monilia. Preventive measures include regular thinning of the crown, suitable location, compost fertilization, wound closure after cutting and robust varieties such as 'Dönissens Gelbe Krpel' or 'Maibigarreau'.
Shotgun disease and spray spot disease
The most common disease affecting sweet cherries is shotgun disease. This disease, which is caused by fungal pathogens, can begin to manifest itself as early as May. Red-brown spots appear on the leaves. Eventually the spots become holes and the leaves look like they have been shot through with holes. Then they dry up and fall off.
The spray spot disease is similar to the shotgun disease. Here it is smaller spots that make the foliage unsightly. They are reddish to purple in color. You can see the yellowish-white spores of the fungus on the underside of the leaves. This disease can also be transmitted to the fruits of the sweet cherry.
Monilia – another bad mushroom
Monilia is well known and also likes to appear with sweet cherries. Here the flowers, leaves, shoots and/or fruits are attacked. The flowers turn brown in spring and fall off. The new shoots dry out and the leaves are shed. A radical pruning helps here.
Other diseases of sweet cherries
Diseases such as fruit tree canker, bacterial blight and rubber foot occur less frequently. The fruit tree canker (a fungal pathogen) attacks the wood and bark. Thickenings then form. Bacterial burn, which can manifest itself in depressions on the branches, can lead to the dreaded rubber foot (tissue dissolves and the cherry gradually dies).
How can you prevent the diseases?
Stress and nutrient deficiency are mainly considered to be the cause of diseases in sweet cherries. Give the sweet cherry the opportunity to build up natural self-protection. This means: Do not choose heavily overbred varieties, no artificial fertilizers and no chemical fungicides, etc.
The following measures have a preventive effect against diseases:
- Thinning the crown regularly
- Plant the sweet cherry in a location that is conducive to it
- fertilize with compost or effective microorganisms
- Leave leaves lying around in autumn (humus formation)
- Larger cuts should be treated with wound closure agent (€24.00 on Amazon)
Tips & Tricks
Some varieties such as 'Dönissen's Yellow Cartilage', 'Maibigarreau' and 'Tilgener's Red Heart Cherry' are particularly robust against diseases.
