It is not uncommon for forsythia to be afflicted by the insidious Monilia lace drought or Verticillium infection. Then act quickly.
Your forsythia (Forsythia) in the garden is looking sad? Is it wilting even though you water and fertilize the plant regularly? The shrub may then be infected by the pathogen Monilia laxa or by a Verticillium infection. Here's how to recognize these diseases and what steps you can take to protect each plant and your garden.
Monilia peak drought: clinical picture and immediate treatment
If your forsythia start to wilt suddenly at the tops during or after flowering, they are probably infested with the fungus Monilinia laxa. Known as monilia lace drought, the wilt extends 20 to 40 centimeters on the branches. It captures flowers and leaves that either fall off the plant directly or remain hanging limp.
Measures against Monilia peak drought:
➭ In damp weather, the fungus can sometimes be seen as a yellowish to gray coating on the branches. But don't worry, if you cut back the affected branches immediately, there is a very good chance of healing. To do this, you can cut at least 15 centimeters beyond the visibly diseased area into the he althy wood. You can also apply fungicides at the time of flowering.
Important:
Dispose of the cut off parts of the plant in the compost bin or with the residual waste. Never throw the branches on the compost. The pathogens can hibernate there and get back into your garden when you use the humus.
➭ Check fruit trees in your garden for a possible infestation of Monilia laxa, which can also show up as either peak drought or fruit rot. You can recognize fruit rot by the ring-like brownish discoloration of the fruit. In the case of stored fruit such as apples, this discoloration can also be shiny black and eventually cover the entire fruit.
➭ Don't cut too hesitantly to ensure a loose plant structureyour forsythia. When planting individually, make sure that the distance between the shrubs is as large as possible.
Verticillium infection: clinical picture and immediate treatment
If your forsythia does not wilt on the tips, but first on older, inner parts of the plant, you may have a Verticillium infection. This dangerous disease comes from the fungus Verticillium dahliae or Verticillium albo-atrum and is a bit more difficult to treat. Unfortunately, an exact diagnosis is only possible with a laboratory test.
Measures against Verticillium infection:
➭ There is a test that gives you clues about a possible illness. To do this, remove the bark from an affected branch. If you notice brownish veins running lengthwise to the wood, a Verticillium infection is very likely. It is best to cut back the affected shrub immediately. Also, remove all fallen leaves and dispose of all plant material in the residual waste or in the compost bin.
➭ If the same symptoms reappear after pruning the forsythia, to protect your garden you should remove all of the forsythia and replace the surrounding soil as well. This is because Verticillium infection can spread to many different plants and, if left untreated, will lead to complete death.