How to Control Root Rot

Imagine nurturing a plant, watching it grow, and suddenly, it starts wilting, leaves turning yellow and eventually, the whole plant dies. You’ve just experienced a common but devastating plant disease known as root rot.

Root rot is a condition that, if left unchecked, can severely damage or even kill your plants. Understanding and long-term effective control of root rot is crucial.

Understanding Root Rot

What is Root Rot?

Root rot is a disease caused by various types of fungi that attack the roots of plants, resulting in decay and death. It’s a silent killer, often not detected until it’s too late, leading to irreparable damage. The disease commonly affects a wide array of plants, including popular ones like roses, tomatoes, lilly pilly, and more.

Causes of Root Rot

Root rot primarily occurs when the plant’s root system is overwatered, causing a lack of oxygen and making it a breeding ground for fungi like Phytophthora spp., Pythium spp., Rhizoctonia spp., and Fusarium spp. Other factors contributing to root rot include poor soil drainage, compacted roots, and over-fertilisation.

Symptoms of Root Rot

Identifying root rot early can often be the difference between saving a plant or losing it. Early symptoms include wilting, yellowing leaves, stunted growth, and reduction in yield. Advanced symptoms include dark, mushy roots, a foul smell, and eventually, the plant’s death.

The Science Behind Root Rot

Root rot, at its core, is a battle for oxygen. Plant roots need oxygen to function and grow. When overwatering occurs, it fills up air spaces in the soil, leading to an oxygen-deprived environment where harmful fungi thrive. These fungi infect the roots, hindering their ability to absorb water and nutrients, affecting the overall health and growth of the plant.

Methods to Prevent Root Rot

Proper Watering Techniques

Prevention is always better than cure. One of the key methods to prevent root rot is by adopting correct watering techniques. Ensure the plant is watered according to its specific needs, and avoid overwatering. Use a moisture meter if necessary to check the soil’s moisture level before watering.

Appropriate Soil and Drainage

Soil type and proper drainage play a vital role in preventing root rot. Opt for well-draining soil or potting mix when possible, or amend heavy clays with gypsum and organic matter.

Regular Plant Inspection

Conduct regular inspections of your plants. Look out for early signs of root rot, such as wilting or yellowing leaves. Early detection can often lead to successful treatment.

Treating Root Rot

If you detect root rot, don’t despair. Firstly, stop watering the plant immediately. Remove the affected plant and cut away any dark, mushy roots. Let the plant dry out before replanting in fresh, well-draining soil.

Chemical Treatments

Chemical treatments, like fungicides, can be effective in treating root rot. However, they should be used as a last resort due to their potential environmental impact.

Natural Treatments

Natural treatments, such as using beneficial fungi and bacteria to fight off the harmful ones, can also be effective in some cases. These are not a replacement for optimising the growing environment, but a tool to use in conjunction with cultural and genetic control methods.

Select Good Genetic Stock

Not all plants are bred the same. Some cultivars of the same species will often differ in their ability to tolerate wet feet and phytophthora in the environment. Ozbreed have extensively studied certain plants’ capacity to thrive in wet feet over the years. You can learn which plants have performed well and which have failed:

Daniel’s Wrap

Understanding, preventing, and treating root rot is crucial for maintaining healthy plants. It requires regular attention and care, but with the right knowledge and practices, you can successfully keep root rot at bay. Apply what you’ve learned today to your gardening practices, and enjoy the satisfaction of healthy, thriving plants.