The Content Of The Article:
- Spider mites on chrysanthemums
- Leaf spot disease on chrysanthemums
- Prevention: Site selection and care
Even rugged and resilient plants such as chrysanthemums can be attacked by pests and diseases. If you react in time, you can help the plant.
Chrysanthemums are originally from Asia and are among the most important ornamental plants. One of the main reasons for the high popularity level is the ease of care and the robustness of the plant. Nevertheless, it can happen that make small pests in the care of pests on the plant wide. Those who react quickly and treat the pest infestation or the disease have a good chance that the chrysanthemum will recover.
Spider mites on chrysanthemums
The tiny spider mites are barely visible to the naked eye. Check the undersides of the leaves regularly - if there is a whitish web, then the spider-like, yellow, green or red animals are at work.
➔ In case of low infestation spray the plant with a biological agent based on rapeseed oil. We can recommend you the Naturen Schädlingsfrei (for example, here available). The oil sticks to the respiratory organs of the spider mites and prevents further reproduction. Pyrethrum-based sprays also help.
➔ Even wrapping in foil can help. Spray the chrysanthemum copiously with water and wrap the visible part of the plant in foil. Moist heat forms in the film. The spider mites can not tolerate this and are destroyed. The film treatment takes about two weeks.
➔ If the infestation is extremely strong, it is worth the purchase of predatory mites. The PP predatory mites eat spider mites and naturally ensure that the plant is freed from the pests. When using predatory mites should also be a humid climate prevail - the temperature should be above 18° Celsius during the day.
Leaf spot disease on chrysanthemums
If you spot yellow, reddish, or brownish spots on the chrysanthemum leaves, the plants have a fungal disease. So that it does not get that far, you can preventively splash with a tea infusion of onion skins or field horsetail. Many chrysanthemum species are largely resistant to fungi, but there is no one hundred percent protection.
The cause of the leaf spot disease are various fungi, for example Septoria, Alternaria and Ascochyta. The mushrooms settle on the underside of the leaves with their fruiting bodies, on the upper side of the leaves show the spots. In case of strong proliferation, the leaves look perforated, one then speaks of "shotgun disease".
If only individual parts are involved, remove them generously. Disinfect the secateurs after each cut with spirit, so that no further mushroom spores can spread and multiply. A biological control or home remedies are unfortunately not effective.
Highly infested plants treat with an anti-fungal agent. Particularly suitable are broad-spectrum fungicides, since it is often a combination of several types of fungi.
»Only alternative: disconnect from the plant. But please do not dispose of them on the compost pile!
Prevention: Site selection and care
Dry, light and sheltered, this is the ideal location for chrysanthemums. If you plant several perennials, make sure you have enough space. A dry foliage protects against fungal infestation, so only water chrysanthemums from below.
- Whitish web on the leaves: Spider mite infestation
- Remedy: spraying with rapeseed oil-based agents or film treatment
- Blotches on the leaves: leaf spot disease, caused by fungi
- Remedy: Remove infected stalks and leaves, spraying with broadband fungicide