Common Kalanchoe Diseases (And How To Treat Them)

Kalanchoe plants, with their vibrant blooms and striking foliage, can brighten up any room. However, like any other plant, they are susceptible to various diseases that can threaten their health and beauty. While it might seem daunting to tackle these issues, fear not—understanding common kalanchoe diseases and knowing how to treat them can make all the difference.

In this article, we'll explore some of the most prevalent diseases that affect kalanchoe plants, offering step-by-step advice on how to recognize and treat each one. By the end, you'll be well-equipped to nurse your plant back to health and keep it thriving.

Powdery Mildew: A Fungal Foe

Powdery mildew is a common fungal disease that attacks many types of plants, including kalanchoe. It appears as a white, powdery coating on the leaves, stems, and sometimes flowers. While it might look like harmless dust, it can severely weaken your plant if left untreated.

So, how do you spot powdery mildew? Look for white patches on the leaves, which often start on the lower parts of the plant. These spots can expand and become more noticeable over time, making the leaves curl and turn yellow.

To treat powdery mildew, try the following steps:

• Remove affected leaves: Carefully trim away any leaves that show signs of mildew. This helps prevent the spread to healthy parts of the plant.
• Improve air circulation: Ensure your plant isn't overcrowded with other houseplants. Good airflow can help reduce humidity around the plant, making it less hospitable to fungi.
• Use a fungicide: If the mildew persists, apply a fungicide specifically designed for powdery mildew. Follow the instructions on the label for the best results.

Powdery mildew thrives in warm, dry conditions, so keeping your kalanchoe in a well-ventilated area with moderate humidity can help prevent future outbreaks.

Root Rot: The Silent Killer

Root rot is a sneaky disease that often goes unnoticed until significant damage has occurred. It's caused by overwatering, leading to waterlogged soil and the decay of root systems. This can cause your kalanchoe to wilt, despite having plenty of water.

To check for root rot, gently remove your plant from its pot and inspect the roots. Healthy roots should be firm and white, while rotten roots will appear brown, mushy, and smell musty.

If you suspect root rot, here's what you can do:

• Remove affected roots: Trim away the rotten parts with sterilized scissors. This helps stop the spread of decay.
• Repot your plant: Transfer your kalanchoe to fresh, well-draining soil. Consider using a pot with drainage holes to prevent future waterlogging.
• Adjust your watering habits: Allow the top inch of soil to dry out between waterings. This can prevent excess moisture from accumulating around the roots.

Remember, kalanchoes are succulents and prefer dry conditions. It's always better to under-water than over-water them.

Leaf Spot: Small Spots, Big Problems

Leaf spot disease is characterized by small, dark lesions on the leaves of your kalanchoe. These spots can eventually lead to leaf drop, which can weaken the plant and stunt its growth.

Leaf spot is typically caused by fungal or bacterial pathogens, often due to excessive moisture or poor air circulation.

To manage leaf spot, consider these steps:

• Remove infected leaves: Cut away any leaves showing signs of spotting. This prevents the disease from spreading to healthy foliage.
• Avoid overhead watering: Water your plant at the base to keep moisture off the leaves. Wet leaves are more susceptible to fungal infections.
• Use a fungicide or bactericide: Depending on the cause, a suitable treatment can help control the disease. Follow product instructions carefully.

Maintaining good plant hygiene, such as cleaning fallen leaves and debris, can also help prevent leaf spot from taking hold.

Pest Problems: Unwanted Visitors

While not a disease itself, pest infestations can lead to significant health issues for your kalanchoe. Common pests include aphids, mealybugs, and spider mites, which can damage the plant by sucking its sap.

Signs of an infestation include distorted leaves, sticky residue, or visible pests on the plant. To deal with pests, try these approaches:

• Manual removal: Gently wipe off pests with a damp cloth or use a soft brush for more stubborn invaders.
• Introduce beneficial insects: Ladybugs and predatory mites can help control pest populations naturally.
• Apply insecticidal soap: This can effectively kill pests without harming your plant. Be sure to cover all parts of the plant with the solution.

Keeping your plant healthy and stress-free can make it less attractive to pests. Regularly check for signs of infestation so you can act quickly if needed.

Downy Mildew: The Unexpected Threat

Downy mildew, although less common than its powdery counterpart, can still pose a threat to kalanchoe plants. It's caused by a different type of fungus and typically thrives in cool, damp conditions. You might notice yellowish spots on the upper side of leaves with grayish, fuzzy growth on the undersides.

Here's how to handle downy mildew:

• Improve air circulation: Like powdery mildew, downy mildew benefits from stagnant air. Moving your plant to a more ventilated space can help.
• Remove affected foliage: Trim away any infected leaves to stop the spread.
• Apply a fungicide: Products designed for downy mildew can help control the disease. Follow instructions for safe and effective use.

Since downy mildew thrives in wet conditions, keeping your kalanchoe dry and ensuring good air circulation can prevent this disease from taking hold.

Bacterial Soft Rot: A Smelly Situation

Bacterial soft rot is a particularly unpleasant problem, often recognized by a mushy, foul-smelling decay of plant tissues. It typically occurs in warm, humid environments and can spread rapidly if not addressed.

If you notice soft, discolored areas on your plant, it might be time to take action:

• Isolate the plant: To prevent the spread to nearby plants, isolate the affected kalanchoe immediately.
• Remove infected parts: Cut away any soft, rotting areas with sterilized scissors, being sure to sanitize them between cuts.
• Reduce humidity: Lower the humidity around your plant and improve air circulation to create a less favorable environment for bacteria.

In severe cases, you might need to discard the plant to protect others in your collection. Always practice good hygiene by cleaning tools and pots to prevent future outbreaks.

Anthracnose: A Spotty Challenge

Anthracnose is a fungal disease that causes dark, sunken lesions on leaves, stems, and flowers. If left unchecked, it can lead to significant defoliation and even plant death.

To combat anthracnose, consider these strategies:

• Prune affected areas: Remove any parts of the plant showing signs of infection to halt the spread.
• Ensure dry conditions: Water at the base of the plant and avoid getting the leaves wet.
• Use a fungicide: Apply a product specifically formulated for anthracnose, following the label instructions closely.

Keeping your kalanchoe in a dry, well-ventilated environment can deter anthracnose from taking hold. Regular monitoring can also help catch the disease early.

Botrytis Blight: The Gray Menace

Botrytis blight, or gray mold, is another fungal disease that can affect kalanchoe plants. It appears as gray, fuzzy growth on leaves, stems, or flowers and thrives in cool, damp conditions.

For treatment, try these steps:

• Remove infected parts: Cut away and dispose of any affected areas to prevent the spread of spores.
• Improve airflow: Ensure good air circulation around your plant to reduce humidity.
• Apply a fungicide: Use a fungicide designed to treat botrytis blight, carefully following application instructions.

Avoid overcrowding your plants, as this can lead to the high humidity levels that botrytis blight loves.

Viral Infections: A Trickier Problem

Viral infections in plants are less common but can be particularly challenging to deal with. They often result in distorted growth, yellowing, or mottling of leaves.

Unfortunately, there is no cure for viral infections in plants. However, you can manage the situation by:

• Isolating the plant: Separate the infected kalanchoe from healthy plants to prevent the virus from spreading.
• Maintaining plant health: Keep your kalanchoe as healthy as possible, ensuring it's well-watered and fertilized.
• Practicing good hygiene: Clean pots and tools regularly to avoid spreading the virus unintentionally.

If the infection is severe, you might need to consider discarding the plant to protect the rest of your collection. As always, prevention is the best strategy, so use sterile tools and avoid introducing potentially infected plants to your home.

Final Thoughts

Dealing with kalanchoe diseases can seem overwhelming, but with the right knowledge and approach, you can keep your plants healthy and vibrant. By identifying problems early and taking appropriate action, you can save your plant from harm.

At Cafe Planta, we understand the joy and satisfaction that comes from nurturing houseplants. Feel free to reach out to us via email or Instagram for guidance or to explore our collection of plants and accessories. We're here to help you connect with nature and grow your own indoor oasis.