A rhododendron is loved for its large, brightly colored flowers. The leaves are more of a simple accessory. They don't stand out. However, if stains spread on them, the overall appearance will be dulled for a long time. Is there more danger?

Spotting on the rhododendron leaves is often, though not always, a sign of leaf spot disease

Causes of Spots

When part of the leaf has a different color than usual, it is commonly referred to as spots. It doesn't always have to be a serious illness. Therefore a scrutiny is necessary. In summer it can well be that it is sunburn. But just as well, various fungal pathogens can have caused the stains. For example the following specimens:

  • Cercospora
  • colletorichum,
  • Glomerella
  • Pestolotia

Although they are different pathogens, they are summarized under the term leaf spot disease.

Symptoms on rhododendrons

Leaf spot disease is to be expected especially in warm, humid summers. Different spots may appear. Depending on which pathogen is spreading.

  • the staining can be reddish brown to black
  • round but also irregularly shaped spots are possible
  • they have a yellow, red or black border
  • the leaf spots are small at the beginning
  • they are getting bigger and growing together
  • if there is humidity, they may be covered with mold
  • sometimes leaf fall can occur

Notice:
The yellow flowering hybrid varieties are considered to be particularly susceptible to leaf spot disease.

Combat leaf spot disease

Leaf spot can be effectively controlled if you don't mind using an "environmentally harmful" broad spectrum fungicide. Unfortunately, there are no known effective home remedies. But this disease does not necessarily have to cause great damage. Therefore you can also proceed as follows:

  • Pluck and destroy affected leaves
  • Also discard fallen leaves
  • Cut off and discard badly affected branches

Notice:
Take a closer look at the underside of the leaves to see if you can spot yellow-orange spore beds. Then it is not leaf spot disease, but rhododendron rust. The two diseases are often confused with each other.

Prevent recurrence

Pay a little more attention to the rhododendron the following year. In summer, it should only be watered above the root base so that its leaves do not get wet. Also make sure that you use fertilizer that meets your needs so that the vitality of the plant does not suffer.

tips

Leaf spot disease also occurs on hydrangeas, privet, camellia and many other plants. You should also keep an eye on these plants.

Category:

Vegetable garden