Don't wait, take action! This is the motto that must be followed when dealing with tendril disease. Because if it gets hold of all the tendrils, it can completely destroy the blackberry bush. It is therefore important that you know the typical symptoms of the disease and discover them in good time.
How do I combat vine disease on blackberries?
Take action immediately as the vine disease spreads quickly. Cut off all infected canes and dispose of them as household waste, tightly sealed in a plastic bag. Carry out preventative checks from spring onwards and ensure that your blackberries are not damp.
What causes vine disease?
Blackberry vine disease is caused by thefungus Rhabdospora ramealis. It is also known as Septocyta ruborum. It overwinters in the host tissue as mycelium and, from March onwards, breaks through the epidermis of the tendrils with ripened fruiting bodies. From April to August its spores are spread further with the rain. Only young, tender shoots are infected.
When does vine disease appear and how does it show itself?
The tendril disease, often also called rod disease, shows itself like this:
- dark green, pinhead-sized spots appear on shoots in summer
- first close to the ground, later higher up
- first turn reddish, then brown with a red edge
- grow to about 2 cm in diameter, flow into each other
- finally large parts of the bark are covered
- the damage will break down the following spring
- many black tubercles (pycnidia) become visible
- 1 mm long white spore tendrils are formed (in humidity)
- affected tendrils develop normally
- die later from the tip
- Leaves, flowers and fruit bases change color and wilt
How can I save the blackberry bush?
Apart from generously removing and disposing of all diseased plant parts, there is not much left to do. To combat a very severe infestation, you canadditionally use an approved fungicide between April and August.
How can I prevent vine disease on blackberries?
Plant the blackberry variety 'Chester Thornless' or 'Thornless Evergreen', both of which are considered to be less susceptible. Otherwise, these measures will help to avoid conducive moisture:
- choosing an airy location
- Avoid shadows
- Maintain sufficient planting distance
- cut and trim regularly
- attach new tendrils to the climbing aid early on
If you regularly check your blackberry plants for symptoms of disease from spring onwards, you can also discover many other diseases and pests such as lice or blackberry gall midges at an early stage.
Tip
Do not confuse symptoms of vine disease with frost damage
In very harsh winters it can happen that some blackberry vines freeze and then dry up. They don't look much different than specimens destroyed by cane disease. Be sure to pay attention to the pycnids (black bumps), which you can use to reliably diagnose the vine disease.
