It's so devastating when the actually velvety green mint leaves are covered in brown spots. There are two diseases that cause such damage. You can find out what these are and how to combat them here.
What to do if you have brown spots on mint leaves?
Brown spots on mint leaves can be caused by mint rust or leaf spot. To combat both diseases, cut the infected mint back to the ground, leave a sleeping eye and dispose of the cuttings by burning.
Main suspect: mint rust – this is how to combat it
Within the order of mushrooms, a species of fungus has specialized in attacking mint species. They are rust fungi that can infect a plant throughout the growing season. The spores act as parasites so that they do not kill the tissue. Rather, brown spots form around the infection sites. The entire plant is therefore not threatened by mint rust.
You will appreciate the rapid growth of your peppermint or other variety when it is infested with rust fungi. This is how easy it is to fight the disease:
- cut the infected mint back to the ground
- leave only one sleeping eye on the plant
- from here it sprouts again he althy
- Do not dispose of the clippings in the compost, but burn them
Effective prevention
To make it more difficult for fungal spores to infest a mint, the soil in the bed should be loosened repeatedly. In addition, regular weeding is an effective preventive measure. Each time you water, avoid wetting the leaves. Moist leaves particularly attract the pathogens.
Leaf spot disease shows no mercy
For laypeople, it is almost impossible to visually distinguish between mint rust and leaf spot. There is no need to take a closer look at the distinguishing features because the control methods are the same. Regardless of where the brown spots on mint come from, radical pruning is the best approach.
Tips & Tricks
The most efficient prevention against any diseases on mints is to rotate crops in the bed every year. It should be transplanted or repotted at least every two years. No other type of mint or mint family must have been cultivated at the new location in the previous four years.
