How Do I Know if My Plant Has Root Rot?

Root rot is something I hear people worrying about quite a bit, especially when they notice a yellow leaf, drooping foliage, or a plant that seems to have slowed down. And I understand why. We spend so much time looking at the leaves and watching our plants grow that it's easy to forget how much is happening underneath the soil.

One of the things I really enjoy teaching is how to understand the root system. Those roots are doing an incredible amount of work, and once you become familiar with what healthy roots look and feel like, it's much easier to recognize when something needs attention.

So let's talk about what we're actually looking for and how we can check our roots while keeping as much of that healthy root system intact as possible.

What Do Healthy Roots Look Like?

If you've ever taken a few different plants out of their pots, you've probably noticed that their roots can look completely different. Some are white or cream-colored, others are tan or brown, and some develop darker outer surfaces as they mature. Even roots on the same plant can have different appearances depending on their age.

I pay quite a bit of attention to how those roots feel. Healthy roots generally have a nice, firm structure. You'll often see smaller lateral roots branching away from the larger ones, and sometimes you'll notice fresh root tips developing. I love seeing that because it's a good indication that the plant is actively growing new roots.

Those smaller roots are especially valuable. They contribute a tremendous amount of surface area for absorbing water and nutrients, and they're part of the established system that's already supporting your plant.

That's one of the reasons I'm so particular about protecting healthy roots when I repot. When you've got a beautiful, functioning root system, there's a lot of value in preserving what the plant has already grown.

What Happens When Roots Begin to Rot?

When roots begin deteriorating, you'll usually notice changes in their texture and structure. They may become soft, mushy, or fragile. Sometimes, when you gently handle a damaged root, the outer tissue slips away and leaves a thin strand behind.

You might also notice an unpleasant smell coming from the growing medium, particularly when the root zone has remained excessively wet for a long time.

I think it's important to understand that root color alone tells us very little. Some plants naturally have brown roots, and older roots may develop darker surfaces while remaining perfectly healthy. I'm much more interested in whether the tissue is firm and maintaining its structure.

When roots begin losing that structure, they also begin losing their ability to function properly. That can affect how much water and nutrition the plant is able to absorb. And it explains why you can sometimes have a plant with drooping leaves even though there's plenty of moisture in the pot.

That's where our growing environment comes into the conversation.

Why Water and Oxygen Matter So Much

I talk about the relationship between water and oxygen quite a bit because both are essential to healthy roots.

When we water our plants, moisture moves through the growing medium and fills some of the spaces between the soil particles. As that moisture drains and the growing medium begins to dry, air becomes available in those spaces again.

Our roots need that oxygen to carry out normal respiration and support healthy growth. When the growing medium stays heavily saturated for too long, oxygen becomes less available, and the roots can begin struggling. Those conditions can also encourage organisms associated with root disease.

This is part of why I use the growing medium I do at Rooted. My typical mix is equal parts succulent soil, coarse orchid bark, and grade 3–4 perlite. I work with a small-to-medium chunky texture because I want the growing medium to hold useful moisture while still providing air spaces around the roots.

I'm also watching how quickly my plants move through their moisture.

For many of the tropical foliage plants I grow, I like to see that watering cycle happening in approximately seven days. It's a practical timeframe I use to help evaluate how the plant and its environment are working together. Different plants have different moisture requirements, so I'm always considering what I'm growing.

If a plant that normally dries in about seven days starts taking twelve or fourteen, I'm curious about what's changed.

Maybe it's receiving less light as the seasons change. Maybe it's sitting farther away from a window than it needs to be. Or perhaps the root system is relatively small compared with the amount of growing medium inside the pot.

Light plays a tremendous role in how actively plants grow and use water. If your plant is taking longer to dry than you're accustomed to, checking the light reaching its leaves is a great place to begin.

I like looking at these relationships because they help us understand why our plants are behaving differently instead of guessing based on what we're seeing above the soil.

When Should You Take a Look at the Roots?

Let's say you've noticed several leaves turning yellow, the plant has slowed down, and the growing medium seems to be staying wet much longer than usual.

Those are all useful observations, and together they may give us a reason to take a closer look underneath the soil.

When I check a plant's roots, I like to gently slide the root ball out of its nursery pot. That allows me to see what's happening around the outside and bottom of the root system while keeping the established roots and growing medium together.

I'm looking at how those roots are developing. Do they feel firm? Are there smaller roots branching through the growing medium? Is there healthy new growth? Are there sections that have become soft or started breaking down?

I'm also paying attention to the growing medium itself. How much moisture is it holding? Is it still allowing air to move through the mix? Does the root system appear to be growing comfortably in the space available?

Sometimes you'll slide a plant out of its pot and find a beautiful, healthy root system. That's wonderful! You can gently place it right back into its container and continue evaluating the other parts of its growing environment.

And if you discover some damaged roots, you'll have a better understanding of what needs attention.

What if You Find Damaged Roots?

When I find roots that have clearly deteriorated, I want to protect as much of the healthy root system as possible. Any roots that have become soft and decomposed can be carefully removed while preserving the firm, functioning roots around them.

How much healthy root tissue remains is important because that's what the plant has available to support recovery and begin producing new growth.

I also want to understand what the roots have been growing in. If the growing medium has deteriorated, become compacted, or is holding excessive moisture, changing those conditions may be part of helping the plant recover.

The size of the pot matters here, too. We want a container that's appropriate for the root system we actually have.

You've probably heard me talk about slip-potting. Whenever I have a healthy, established root ball, I prefer to preserve it and allow the roots to grow naturally into the surrounding fresh mix. There's a lot of valuable root development happening inside that original root ball, and I want to keep it intact.

If we're dealing with damaged roots or deteriorating growing medium, we can carefully address the affected areas while protecting the healthy portions that remain.

After that, I want to make sure the plant is receiving appropriate light, has a growing medium that supports healthy roots, and is being watered according to the moisture it's actually using.

Depending on how much root damage has occurred, recovery may take some time. As new roots develop, you may begin noticing changes in how the plant uses water, how the remaining foliage looks, and eventually how it produces new growth.

Getting Comfortable With Your Root Systems

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