If the leaves change color, do not grow properly and the whole plant begins to worry, the peppermint is affected by a disease. How you can recognize illnesses and what you should do now.
What diseases can affect peppermint and how do I fight them?
Common diseases of peppermint include peppermint rust, powdery mildew, rootstock and stem rot, and verticillium wilt. To combat them, affected shoots should be cut off, the location changed and resistance-promoting measures such as regular transplanting carried out.
Common diseases of peppermint
- Peppermint Rust
- Mildew
- Root and stem rot
- Verticillium wilt
Peppermint Rust
This is a fungal disease that is noticeable through thickened and dried shoots and spots on the leaves. Peppermint rust occurs quite often and is encouraged by excessive moisture.
If you noticed the infestation in time, cut all shoots down to the ground. Make a decoction of field horsetail by placing fresh herb in water for two to three days and then straining it out.
Spray the infected peppermint plant several times with the broth. If the infestation is advanced, the only solution is usually to tear out the peppermint completely and plant or sow new herbs in another location.
Mildew
If the leaves show a gray-white coating, powdery mildew is responsible. It occurs particularly frequently in damp weather.
Cut off all affected shoots close to the ground. Fertilize the plants with nettle manure to strengthen them.
Root and stem rot
You can recognize this disease when the bottom of the peppermint stems become soft and rot. Rot occurs when the peppermint is too wet. Make sure that irrigation and rain water can drain away.
Verticillium wilt
If the leaves hang limply and begin to wilt even though you water regularly, the peppermint is suffering from verticillium wilt. It is caused by a fungus and is difficult to combat. It can therefore make sense to completely dispose of infected plants.
Prevention is the best protection
In a favorable location, peppermint grows vigorously, so diseases don't bother it so much. Basically, you should make sure that you do not plant the peppermint too densely, that the soil is permeable and contains enough nutrients.
Tips & Tricks
To make your peppermint more resistant to diseases, never keep the herb in one place for too long. Repot the plants every three to five years. This means that the pathogens of peppermint diseases cannot spread as quickly.
