Do you spot white fungus on your jade plant? It can be Powdery Mildew on Jade plant, a fungal disease associated with cool, humid conditions and lack of good air circulation. You cannot cure the infected leaves; you should pick them off and place them in the trash. However, you can control their extension on your jade plant and their spread to other plants.
I’m a horticultural consultant who has a PhD in Plant Protection Science. So, keep reading to tell you how to get rid of and prevent Powdery Mildew on your Jade Plant according to my experience. First, let’s get familiar with the Powdery Mildew fungus.
Who is Powdery Mildew Fungus?
➡ I provided information about the causal agent of powdery mildew on jade plants here, those who are busy can only read the Functional parts highlighted in blue shades.
Powdery Mildew is a common fungal disease that infects the surfaces of the leaves, stems, flowers and sometimes fruits of the plant. Various fungus species can cause this disease. They all have their own narrow range of host plants but present the same signs and symptoms. For example, Begonia powdery mildew only spreads to other begonias.
The causal agent of powdery mildew on jade plants is Oidium kalanchoes. The taxonomy and phylogeny of Oidium kalanchoes and its synonymy with Erysiphe sedi have recently been clarified by Götz et al. (2019).
Oidium kalanchoes can infect only the Crassulaceae family such as the Jade plant (Crassula ovata). Hence, if you spot the sign of Powdery Mildew on your Jade plant, it can infect other plants in Crassulaceae like Aeonium, Echeveria, Crassula (), Kalanchoe, Sempervivum, and Pachyphytum, and vice versa. So, you must isolate the infected plant to protect other plants from the Crassulaceae family.
This fungus produces thousands of tiny spores which make a powdery appearance on the leaves of infected plants. The spores of powdery mildew are air-borne and spread most quickly in humid environments. Every tiny spore can infect the same genus or family as the infected plant. So, it is vital to control powdery mildew on your jade plant before it gets out of hand as it can be fatal to weaker plants.
What Does Powdery Mildew Look Like on Your Jade Plant?
Now, come on to distinguish Powdery Mildew correctly. Its symptoms are:
- Dust-like, light-coloured, white spots or patches on leaves, stems and/or new growth. This may be confused for dust or dirt at first, but if you wipe it away, it’ll come back.
- It is also may be similar to Botrytis (grey mold) on the Jade plant, I recommend reading my other post to distinguish them.
- It will turn to withering and drying leaves, yellowing leaves, disfigured leaves and new growth.
Some people confused Powdery mildew with mealybugs on the Jade plant, I discussed it in my other post.
How to Treat Powdery Mildew on Jade Plant?
As I told you above, once a leaf of your Jade plant is infected, it cannot be cured. Your best option is to pick off all infected leaves and place them in the trash. Then move your plant to a location where it gets better air circulation and light for stronger regrowth and faster drying.
I have all my jades in a South/West window and they are extremely happy. Keeping plants away from cold drafts and watering early in the day so the foliage has time to dry off can also help to prevent this disease. Don’t allow the jade leaves to get wet.
If the above remedies cannot control the Powdery Mildew on your Jade plant you have to use fungicides, in the following, I listed some that are effective on Powdery Mildew.
Sulfur or Copper-Based Fungicide
Apply sulfur or copper-based fungicides to prevent infection of susceptible plants. For best results, apply early or at the first sign of disease. Spray all plant parts thoroughly and repeat at 7-10 day intervals up to the day of harvest.
Potassium Bicarbonate
Green Cure Fungicide contains a patented formula of potassium bicarbonate — commonly used in food products — that kills many plant diseases on contact and provides up to 2 weeks of residual protection.
Baking Soda
Baking soda is one of the best home remedies for treating powdery mildew. For this method, 1ix 1 tablespoon baking soda and ½ teaspoon liquid soap in 1 gallon of water. Transfer it into a spray bottle and spray the tops and underside of leaves and any other affected areas.
Although this works best as a preventative measure, it’s also known to be effective on existing powdery mildew infections as well. I recommend reading my other post “Get rid of any mold on Jade plant“.
How can I prevent Powdery Mildew on my Jade Plant in the Future?
I, as a horticultural consultant, believe preventing a disease is easier than treating an infected plant. Here are things I do to prevent Powdery Mildew on my Jade plant:
- I always check any plants before bringing them to my home so they are healthy and not infected with any fungi or pests.
- I avoid exposing my plants to excessive drought or imbalanced watering. I found out it is a bad manner which makes my plants sensitive to diseases. For example, a plant that is exposed to drought will be more at risk of being infected with powdery mildew, especially if it’s fluctuating between being heavily watered and being allowed to dry out too much.
- I fertilize my Jade plant. Weakened plants are more susceptible to infection from fungi and other pests and plant diseases.
- I repot your plants before they get root-bound, it makes my plant weak.
- I put my Jade plant near a south-facing window with bright indirect sunlight and perfect air circulation.
- Powdery mildew goes into dormancy during colder seasons and then starts to spread and grow during spring to early summer when the days are beginning to get warmer. Because of this, I keep an eye on my Jade plants during this time and check them regularly for early signs to try and stop Powdery Mildew from spreading.
Conclusion
Powdery Mildew on Jade Plants is caused by the fungus Oidium kalanchoes (Erysiphe sedi) and can infect other plants in the Crassulaceae such as Aeonium, Echeveria, Crassula (), Kalanchoe, Sempervivum, and Pachyphytum.
Curing the infected parts is impossible, so, removing them helps you to control the spreading of disease to healthy parts and other plants. For severe infections, spray your plant with fungicides like potassium bicarbonate or Baking soda. You can ask me your questions in the comments, I will help you as soon as possible.
Elahe Rabiei
Hi, I’m Elaheh. My Academic major is plant protection, and houseplants are my expertise. As a houseplant lover, my house is full of indoor plants and it is my passion to take care of them. Hence, I’m here to share my knowledge and experience about growing healthy houseplants. I am also a plant protection advisor, so feel free to ask me any questions you may have.