The Content Of The Article:
- Which plants are affected?
- How to recognize an infestation?
- Causes of infestation with Malvenrost
- Prevent Malvenrost
- Fight Malvenrost
If red pustules are spreading on hollyhocks, you have to act fast. Because this is a fungal disease that can spread throughout the garden.
Anyone wandering through a cottage garden will definitely find a plant here: the hollyhock. These roses grow up to 2 meters high and fit perfectly into a cottage garden with their many colorful flowers. Of course, she only looks beautiful when she thrives magnificently. As a rule, that is the case, but it can sometimes happen that it is attacked by an illness. And one is particularly destructive: we are talking about the malvenrost.
Which plants are affected?
Mallow rust is a fungal disease that can occur in the spring. So then, when the first foliage has formed. However, this fungal disease affects not only hollyhocks, but also other mallow and summer flowers. Among other things, for example, silver linden, rose marshmallow and Bechermalven.
How to recognize an infestation?
Hollyhocks are immediately captivated by their beauty. But once the malvenrost has struck, it quickly puts an end to beauty. In the event of an infestation, the leaves on the top of the leaves are covered with brown to yellow spots and reddish spots on the underside that look like pimples or pustules. That alone does not look pretty. If the infestation is strong, the leaves are still brown and die. If they then fall to the ground and they are not disposed of early, the Malvenrost attacks other, neighboring plants.
Causes of infestation with Malvenrost
Often you get the Malvenrost when buying a young plant into the house. When buying a plant, always make sure that it has no defects or spots. However, the mallow rust often breaks even if the leaves of the plant are always moist and can not dry out.
➤ If you want to do something proactively against the malvenrost, you should cut off the plants near the ground in autumn, dispose of all plant remains and pile the soil around the plants. However, it is important that you do not dispose of the plant residues on the compost, but in the household waste, so that the fungal disease can not spread.
Alternatively, you can also work with bark mulch. But you have to remove this in the spring.
➤ The Malvenrost occurs especially in two- and multi-year old Hollyhock. A good supply of nutrients supports the health of the flowers. Fertilize so often with compost.
➤ On top of that, it is important that you water the mallow family so that the leaves are largely protected from moisture.
➤ When planting, always ensure a generous distance between the plants so that the air can circulate well and dry out damp leaves more quickly.
As soon as the striking spots appear on the leaves in the spring, you must cut them off immediately and dispose of them. Then it is advisable to treat the leaves with a slurry of bracken. Put one kilogram of bracken into a bucket and add ten liters of rainwater. Let stand for three days and then inject undiluted on the affected plants. Do not forget the underside of the sheet! If the infestation does not get better, repeat the process again after about two weeks.
If that does not help, you will unfortunately have to resort to chemical control agents. Helpful are e.g. Fungicides against rust fungus or a universal fungus-free. Recommended is, for example, Compo Duaxo Universal Mushroom-free (available here). It stops the spread of fungal diseases and protects against a new case.
Never plant mallow plants in the same place. The fungus can eventually survive in the soil and so attack the new mallow family. Therefore, select a new location year by year.