Roses get brown spots

Fungal infections cause brown spots on roses

Brown spots on leaves or shoots are usually the result of a fungicidal disease, for which various pathogens come into question. The treatment is carried out by a strong cut back, if the infestation is severe, it is often necessary to spray with fungicides. The vast majority of mushrooms feel particularly comfortable in damp weather, which is why roses generally in an airy location should stand - there the leaves can dry off faster when it rains.

Wrong mildew

Downy mildew is noticeable by rust-red spots both on the leaves and on the shoots. Problematic with wrong mildew is the fact that the downy mildew fungus penetrates very deeply into the tissue and is therefore difficult to control.

Rose rust

Rust fungi cause leaf chlorosis (i.e. i.e. the foliage is clearly lighter in color up to yellowing) and rust-colored spots on the leaves. The infected leaves die off and are eventually thrown off, and the whole plant is also considerably weakened.

Black soot

Even with one Infection with Diplocarpon rosae, the causative agent of star soot, the leaves can turn yellow. More typical, however, are the very dark, rather black spots that get bigger and bigger as the disease progresses. Diplocarpon rosae mainly spreads the flight spores.

Leaf and stem rot

This disease is caused by the fungus Cylindrocladium scoparium, which initially causes brown spots on the leaves and soon causes them to die. In addition to the leaves, shoots and roots can also be affected, which eventually begin to rot as the infestation progresses.

Bark blotch disease

Main cause the bark disease is a strong nitrogen fertilization of the roses. The brown to reddish-purple spots appear mainly near the shoot buds.

Prevention is better than cure: Plant hygiene is particularly important

Since fungal diseases are very difficult to fight - after all, the pathogens penetrate deep into the plant tissue and can only be removed with a courageous cut into the healthy wood - you should better be an infestation prevent. This not only includes susceptible rose varieties in spring spray with pesticides, but also to adhere to basic rules of plant hygiene. Leaves - both fallen and still on the bush - should always be disposed of in autumn because the fungal spores overwinter on it and so in the following spring for a new infection care for.