The String of Dolphins plant, formally known as Curio peregrinus or Senecio peregrinus, is a trailing succulent prized for its leaves that resemble miniature leaping dolphins. The signature plump, curved shape of these leaves is maintained by turgor pressure, which is the internal water pressure pushing against the cell walls. When you notice your dolphins are flat, shriveled, or deflated, it is a clear sign the leaves are losing the internal moisture reserves they need to stay firm. This flatness signals a problem with its water uptake or retention, and pinpointing the exact cause is the first step toward recovery.
The Primary Culprit: Dehydration
The most frequent reason the dolphin-shaped leaves flatten is simple dehydration, or underwatering. Since this succulent stores water within its foliage, it is drought-tolerant, but it still requires deep, infrequent watering. You can confirm this issue by checking if the soil is completely bone dry, often pulling away from the sides of the pot. In this scenario, the plant’s root system is healthy, but it has exhausted the water stored in its leaves.
To correct this, you must thoroughly rehydrate the plant, often through bottom-watering. Place the pot in a saucer of water for 30 minutes to an hour, allowing the soil to wick moisture up to the root ball. This method ensures the entire soil volume is saturated, which is more effective than a light pour from the top. Once the soil is saturated, remove the plant and let all excess water drain away, then resume watering only when the soil has dried out again.
The Counter-Intuitive Cause: Root Damage
A cause of flatness is root rot, which is usually the result of overwatering. The symptoms—flat, shriveling leaves—are identical to underwatering because the plant is still suffering from a lack of water, despite the soil being moist. In this situation, the roots are damaged and mushy, making them incapable of absorbing and transporting water to the leaves. The roots drown and then rot, rendering the plant unable to perform its function.
If the soil feels perpetually wet and the stems near the soil line are soft or mushy, you need to inspect the roots immediately. Gently remove the plant and brush away the old soil to check the root system. Healthy roots are firm and white, while rotted roots appear black, brown, and soft. Carefully trim away all damaged roots using clean, sterile scissors and allow the remaining healthy roots to air-dry for several hours. Repot the succulent in a new pot with fresh, dry, well-draining soil, and delay watering for a few days to allow the roots to heal and acclimate.
Ensuring Proper Environment
Ensuring the String of Dolphins is in the correct environment prevents both dehydration and root damage long-term. The plant requires bright, indirect light for at least six hours a day to maintain its compact, curved leaf structure. Insufficient light can cause the leaves to flatten and stretch out as they attempt to increase their surface area to absorb more light for photosynthesis.
The potting medium and container are important for preventing water-related stress. A quick-draining succulent or cactus mix, often amended with perlite or pumice, is necessary to prevent the soil from remaining saturated after watering. The pot must have a drainage hole to allow excess water to escape freely, preventing the stagnant conditions that lead to root rot. Avoid placing the plant near cold drafts or intense heat sources, as sudden temperature fluctuations can shock the plant and increase water loss from the leaves.