Caring for your houseplants correctly is the best defense against disease, but stay vigilant! Here’s how to spot and treat diseases attack your plant.
BOTRYTIS (OR GRAY MOLD)
Gray fluff can be found all over the plant, especially in cool, damp, or crowded conditions.
TREAT It: Water your plant from below to avoid splashing water on the leaves or crown. Remove any affected areas, along with any moldy potting mix, and treat with a fungicide. Water and mist less frequently. Improve ventilation.
CROWN AND STEM ROT
The lower parts of the plant are dark, soft, and rotten, due to a fungal infection. It’s usually caused by excess watering, splashing the base of the stems, or cool conditions.
TREAT IT: You can try to save your plant by cutting out the affected area and treating it with a fungicide. Avoid overwatering, and move the plant to a warmer, well-ventilated spot.
Patches of white dust will appear on the leaves. It’s more likely to occur where plants are crowded together, or underwater plants, or in conditions that are too hot and humid. It’s not fatal but it can weaken your plant.
TREAT IT: Remove the affected leaves, and treat your plant with fungicide. Space plants farther apart to improve airflow.
Look for corky growths on the underside of leaves. Odema is cased by waterlogging, high humidity, and low light.
TREAT IT: Water your plants less, reduce the humidity in the room, and move it to a brighter spot.
Thick black fungus grows on the sticky waste of aphids, whiteflies, scale insects, and mealybugs. It blocks light and the plant’s pores.
TREAT IT: Sponge off the mold with a clean, damp cloth and treat the insect infestation.
Signs include mottled, yellow foliage, distorted growth, and white streaks on the flowers.
TREAT IT: A virus would have been transmitted by insects or was already present on the plant when it was bought. There is nothing you can do to save it.
Brown or black spots on the foliage are often surrounded by a yellow halo. Leaf spots can merge and kill an entire leaf. Caused by bacteria or fungi, they are more likely in damp or overcrowded conditions, or if water has been splashed on the leaves.
TREAT IT: Remove any affected leaves and treat your plant with fungicide. Reduce humidity and space plants more widely.
Caused by overwatering, root rot is a fungal infection of the roots that will lead to yellow, wilting leaves that turn brown, followed by the collapse of your plant. Affected roots will be soft and dark.
TREAT IT: Remove the potting mix to check the roots. You can try to save it by trimming off any affected roots with a knife, leaving any healthy , white roots. Then cut the plant back to allow for the root reduction, treat with fungicide, and repot in fresh potting mix and a disinfected pot.