It’s easy to spot a pest on your plant, but what about the signs of infection? Sometimes these can sneak up on you and suddenly you’re dealing with root rot or soft rot, and that can spell disaster for your leafy babies! Sometimes you can catch a fungal infection before it’s too late for your houseplant, so this blog post will break down the signs of a fungal or bacterial infection and give you tips for treatment. 

Plant stress is a key factor 

We checked in with our grower Wayne to get the down-and-dirty tips on common fungal and bacterial infections in plants. He pointed out that environmental stress and improper conditions are a huge reason why plants may be more susceptible to infection.  

Some environmental factors that may be at play with your plant include: 

• Inactive Climate: Too little air movement 

• Improper Lighting: Light conditions are either too high or too low  

• Water Stress: Over or under watering 

• High Humidity: Too much humidity for a plant that needs a drier environment 

Plants can also be prone to fungal infections on their leaves if you get water on the foliage. Be sure to water the soil only when possible, or water from the bottom by placing your grower pot into the right amount of water at the bottom of your pot or in a sink or dish.  

How to Prevent Root Rot 

Fusarium Root Rot: Fusarium is a common soil fungus with multiple species that can cause rotting symptoms in a plant on roots or stems, especially at a point of a cut or lesion on the plant. Fusarium fungi can also take over dead or dying tissues, which is why overwatering and oversaturating roots can lead to a fast overgrowth of this fungus. 

Pythium Root Rot: Pythium is a bacterial organism that is parasitic in nature and eats decaying plant matter, again making it a prime candidate to turn overwatering into full-blown root rot. Fungus gnats (discussed in our common houseplant pests blog) can send this bacterium from their feet as they move from plant to plant.  

Fusarium and Pythium are both causes of Fiddle Leaf Fig Root Rot, especially in an inactive climate with overwatering. Root Rot can also be caused by overwatering alone without the presence of fungi or bacteria. If your plant’s roots sit in too much water without drying out, they will begin to rot away and the rot can spread to healthy roots even after the soil has dried.  

How to Spot Root Rot: Signs of Root Rot include wilting and discolored leaves as an outside signal that something is wrong with the roots, since the roots cannot properly absorb moisture and nutrients. The roots themselves will appear soft/spongy and deep brown or black.  

How to Treat Root Rot: You need to move quickly when you notice root rot signs. You will need sterilized scissors/shears, new potting soil, bleach, and a fungicide from your local nursery or garden center.  

• Remove the plant from the pot and break off the soil from the root ball. Wash the plant roots under running water to clean the soil off.  

• Use sterilized scissors to trim away rotting roots.  

• Prune back the foliage of your plant. It’s heartbreaking but less foliage means the new smaller root system doesn’t have to work as hard and will have time to grow. Trim back the foliage at about the same rate as you had to remove roots (if you trimmed back ⅓ of the roots, trim back ⅓ of the foliage).  

• Toss the rest of the original soil.  

• Wash the pot with a bleach water solution to kill any fungus or bacteria or replace your pot completely. 

• Dip the roots in a fungicide solution to prevent re-infection.  

• Repot in new, clean potting soil.  

Make sure that your pot has adequate drainage. Wild Interiors® plants are potted in a plastic grower pot that drains into the clay pot below. Dump excess water after watering or remove the plant from their grower pots for watering to make sure no water stays in the pot.  

Soft Rot  

Succulents are prone to a type of bacterial infection called Erwinia Soft Rot, which is the same type of rot that would affect a tomato or other fruits and vegetables. This rot liquefies the inside of the fruit or succulent so that the Erwinia bacteria can digest the plant material. It is a little bit gross, we do not blame you if you’re grossed out!  

Soft Rot grows when the bacteria is introduced to a stress point on the plant. If it falls over and bends a leaf, bacteria can get into the wounded area. You can also introduce bacteria by using scissors or shears that haven’t been sterilized. Always wash your tools before pruning. 

How to Spot Soft Rot: Soft Rot forms at the point of a wound, so it starts by looking like a scab and then the surrounding area turns dark brown or black. You might also notice that the affected leaf or area seems soggy and waterlogged and may seep liquid.  

How to Treat Soft Rot: There is no cure once the Erwinia bacteria has infected the plant, but you can work to prevent Soft Rot by immediately treating any wounds on the plant with a fungicide. Allow the soil to completely dry between waterings to avoid over-watering and keep succulents out of high-humidity locations.  

There’s A Fungus Among Us  

Are there other plant diseases you’d like us to explore? Leave a comment below to let us know.