disease remedies

4 Common Diseases – Plus Effective Remedies

So, You Think Your Plant has a Disease?

You’ve noticed that your plant has turned black and you don’t know what to do. What could it be?  I’ve compiled a list of potential and common diseases PLUS remedies (and prevention tips) to help nurse your plant back to health. Pictures are included to help you identify the particular plant ailment (you can find them at the bottom of the post).


The vast majority of remedies discussed are nearly all non-chemical, as most of these common diseases can be resolved by changing your plant’s watering habits or relocating your plant to a more ventilated area. Nevertheless, some chemical solutions are used. I have compiled a list of resources from the Clemson Cooperative Extension Home & Garden Information Center about the treatments used in this post. Organic chemical solutions are still considered highly toxic to humans and animals. However, less toxic, non-chemical insecticides do exist, including insecticidal soaps and neem oil.


Note: When applying particular remedies, make sure the plant has been thoroughly watered and follow the label’s directions. Some houseplants – including jade plant and certain palms – are sensitive to insecticidal soap. Always spot test before treating the entire plant. In some cases, treatment will have to be repeated multiple times.

Common Diseases

1. Root & Stem Rot
  • Appearance: the base of the stem will turn black and become soft; leaves and branches will noticeably wilt
    • Caused by various fungi, which are dormant in the root and stem and are activated in humid, wet environments
  • Fungi survive in the soil or on infected plant debris and can be spread by wind, splashing water, or the moving of infested soil
  • Remedies (& Prevention):
    • Remove the infected plant and if only a few roots are infected, cut those off – infected roots are dark brown or black in color; repot in new, fresh soil
      • However, once root rot occurs, it is unlikely that the plant can be save (especially if it is a new, weaker plant)
    • To prevent this common disease:
      • Properly water your plant according to its watering needs,
      • Use a soil mix with a high drainage capacity,
      • Choose a container with drainage holes, and
      • Dress the soil with pebbles
2. White Mold
  • Appearance: white, fluffy, cotton-like fungus that grows on top of the soil surface in moist, humid, and over-watered conditions
  • Common sign of poor ventilation
  • It does not harm the plant
  • Remedies: gently remove top layer of soil with a knife and relocate plant to a more open, ventilated space
    • Removal process could send fungal spores into the air, which may trigger allergies or asthma
3. ‘Sooty’ Mold
  • Appearance: fungus turns clear honeydew, which is excreted by aphidsmealybugs, and scales, black or dark green
  • This type of fungus thrives in humid and poorly ventilated environments
  • It does not harm the plant, but the pests that excrete the honeydew do
  • Remedies: remove by wiping a damp cloth over the leaves; then rinse the leaves with clear water
4. Powdery Mildew (Fungus)
  • Appearance: the fungus Oidium causes white, powdery growth or dry, brown, papery leaf spots to grow
  • Initial infections commonly come from fungi surviving in dead or decaying plants
    • This common disease develops quickly in very humid conditions
  • Remedies (& Prevention): remove severely infected leaves and relocate plant to a more open and ventilated space
    • As a last resort, you can use a spray containing sulfur after removing the infected leaves to reduce any future incidences
    • To prevent this common disease maintain proper ventilation and watering to control humidity levels

Gallery of Common Diseases

Having trouble diagnosing your plant? Comment below or email me your plant’s symptoms and a photo!

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