Succulents have tough, drought-tolerant reputations. Their greatest strength, surviving in harsh desert climates where little else can grow, is also their biggest weakness. Succulents are especially sensitive to overwatering, and without an understanding of how to avoid it, many new owners kill their plants by giving them too much love.

This guide dives into why watering can cause so many problems, helps you identify the signs of overwatering early, and provides a few simple tips to keep your succulents alive and thriving for years to come. At Plant & Sip, we see this issue all the time, and the good news is that it is preventable with a few practical habits.

The Physiology of Succulents and Water Retention

To understand why water can kill succulents when used incorrectly, we need to look at how they function physiologically. By definition, succulents are adapted to store water in their leaves, stems, or roots. This allows them to make it through long periods between waterings or rainfall.

Evolutionary Adaptation and Photosynthesis

Unlike most plant species, succulents use a special method of photosynthesis known as Crassulacean Acid Metabolism (CAM). While most plants keep their stomata open during the day to gather carbon dioxide, succulents keep them closed and open them at night instead. This process reduces water loss through evaporation.

Because of these adaptations, succulents use water much more slowly than other houseplants with lots of leaves. Giving them too much water at once provides more than they can use.

The Root System Vulnerability

Fast drainage is another key component of how succulents handle water. Succulent roots are adapted to absorb moisture quickly when it rains. But like all roots, they still need access to both air and water. Imagine how quickly water drains through sand or soil with little organic matter. Not only does the water move through quickly, but air can, too.

When you overwater your succulent in a pot, water pushes oxygen-filled air pockets out of the soil. Instead of air, the roots sit in water. Plant roots need oxygen to function and absorb water through root hairs. Without air, they suffer from hypoxia. When plants experience hypoxia from overwatering, it can lead to root death and can spread quickly.

The Progression of Damage

Once roots begin to die from oxygen deprivation, they become vulnerable to disease and fungi. Species like Pythium and Phytophthora can quickly make a home in a compromised plant, causing root rot that spreads up through the succulent’s body. You may not notice any problems until the stem becomes mushy and begins to rot as well.

Diagnosing Overwatering Symptoms

There are several telltale signs of overwatering to look for if you think your plant has been given too much water recently. If you catch an overwatered succulent early enough, you can probably save it. The tricky part is that many people mistake overwatered succulents for underwatered succulents. The symptoms can look similar, but if you assume more water will solve the problem, you only make it worse.

Visual Indicators

One of the first signs of overwatering appears in the leaves. Healthy succulent leaves should feel firm and look vibrant. If your succulent has been overwatered, the leaves may appear translucent, yellow, or an overall washed-out color. This is often due to edema, which occurs when cells take on too much water, swell, and rupture.

Another easy way to tell if you have overwatered your succulent is to feel the leaves. Healthy leaves should feel firm, while overwatered leaves will feel soft and mushy. They may even fall off the plant if you touch them gently. This happens because your succulent is trying to shed affected leaves and focus energy on keeping healthier tissue alive.

Contrast with Underwatering

While underwatering causes succulent leaves to shrivel and deflate (think raisins), overwatering presents a different problem. Too much water causes leaves to swell, but they also turn yellow or translucent and feel soft. Instead of raisins, think water balloons.

Advanced Stages

Once the roots start to rot, you may notice the stem near the soil turning brown or black and feeling soft or slightly squishy. You may also notice a musty smell coming from the soil when you water. That odor can indicate advanced decomposition caused by bacteria or fungi. At that point, the roots are often severely damaged, and the plant may only be salvageable if you cut healthy portions to propagate.