Yellow or wilted leaves, increased occurrence of pests or stunted growth - many symptoms indicate illness in houseplants. But what's really behind it? Only with an accurate diagnosis will you be able to nurse your plant back to he alth. That's why in this article we list the most common diseases of houseplants.
What diseases commonly occur in houseplants?
The most common diseases affecting houseplants include chlorosis, leaf spots, powdery mildew, sunburn, rust fungi and nutrient deficiencies. Symptoms range from yellow or brown leaves, discoloration, spotting, leaf drop and bud loss.
The most common diseases of houseplants
Chlorosis
Chlorosis develops gradually. It is a leaf disease in which roots are no longer able to absorb sufficient iron. The following symptoms occur with the disease:
yellow leaves with green leaf veins
Leaf spots
Waterlogging, cold irrigation water or excessive humidity promote this fungal infection on houseplants, which you can recognize by the following symptoms:
brown, yellow or reddish-brown spots on the leaves
Mildew
Mildew is the result of an aphid infestation. Depending on whether it is powdery mildew or downy mildew, humidity that is too high or too low is responsible for the disease. This is how you recognize mildew:
- small fruiting bodies on the underside of the leaves
- white, sticky coating on the leaves
- Leaves turn yellow
- Leaves curl up
- Ants on the houseplant
Sunburn
Not every plant can tolerate intense sunlight. Watering at midday can also cause damage due to the magnifying glass effect if drops of water remain on the leaves. Typical signs of sunburn are:
light or dark brown spots that have burned deep into the leaf tissue
Rust mushrooms
Drafts and lack of nutrients cause the rust fungus to come into play. Houseplants are particularly at risk when spruce trees grow in the garden or near the property. Conifers are considered intermediate hosts of the rust fungus. On houseplants it expresses itself as follows:
- Spore spots on and under the leaves
- sometimes also on the fruits (if available)
- If the infestation is severe, the spots turn from a rust-like color to deep black
- Leaves fall off
Nutrient Deficiency
Conventional potting soil often does not provide sufficient amounts of important nutrients. Depending on which mineral is missing, the following symptoms arise:
- Potassium: yellow or brown discoloration of the leaves, leaves dry and fall off
- Phosphorus: dirty discoloration of leaves, leaf drop, loss of buds
- Nitrogen: leaves turn yellow, fall off on the lower part of the plant
- Manganese: similar symptoms to chlorosis
