A Guide to Healthy Pothos Roots and Root Rot

The health of a pothos plant is fundamentally tied to its root system. While the trailing vines and glossy leaves are what we see, the unseen network below the soil is responsible for absorbing the water and nutrients necessary for growth. Understanding the needs of these roots is an investment in the plant’s vitality, as a thriving root system ensures it can support lush foliage and grow vigorously.

Pothos Root System Anatomy

A pothos develops two distinct types of roots: subterranean and aerial. The subterranean, or soil, roots are the primary system for nutrient and water uptake from the potting medium. These roots are characteristically fine and fibrous, forming a dense but relatively shallow mass just below the soil surface.

Visually inspecting these soil roots during repotting can offer a clear indication of the plant’s health. Healthy pothos roots are a white or light tan color and feel firm and plump to the touch. In contrast, unhealthy roots signal a problem, often appearing dark brown or even black. They will feel mushy, slimy, or may fall apart easily when handled, which are classic signs of decay.

The Role of Aerial Roots

The short, stubby roots that emerge from the stems at the leaf nodes are known as aerial roots. In the pothos’s native tropical habitat, these roots serve a primary function of helping the plant climb and anchor itself to trees and other surfaces. Their secondary purpose is to absorb a small amount of moisture and nutrients directly from the humid air.

For the indoor gardener, aerial roots present a few management options. They can be left alone, which will not harm the plant. Alternatively, they can be carefully trimmed off at the stem with clean scissors if they become unsightly. A third option is to gently guide these roots down into the potting soil, where they will adapt and convert into functional soil roots.

Identifying and Treating Root Rot

Root rot is one of the most common ailments affecting pothos, and it originates from overly wet soil conditions. The first signs of trouble often appear above ground.

• Leaves turning yellow and wilting, even when the soil feels moist
• Slowed or stunted growth
• Stems that feel soft and mushy near the soil line
• A distinct, foul, or musty odor coming from the soil

To confirm a case of root rot, you must gently remove the plant from its pot for a direct inspection of the root ball. Rotted roots will be dark brown or black and feel soft and mushy, unlike the firm, whitish roots of a healthy plant.

Once root rot is confirmed, action is required to save the plant. Using a pair of sterile scissors or pruning shears, carefully trim away every affected root, ensuring only healthy, firm tissue remains. After trimming, rinse the remaining healthy roots under cool water to wash away lingering soil and bacteria. Finally, repot the pothos into a new container with fresh, well-draining potting mix, but do not reuse the old soil or the unwashed pot.

Promoting Healthy Root Growth

Proactively cultivating a healthy root environment is the best defense against problems like root rot. This begins with selecting the right container. A pot that is appropriately sized for the plant’s root ball and features ample drainage holes is important. Using a pot that is too large can cause the soil to stay wet for too long, as the roots cannot absorb the excess moisture quickly enough.

The soil itself is also important. Pothos roots thrive in a light, well-aerating potting mix. A standard indoor plant mix amended with perlite or orchid bark will improve drainage and allow oxygen to reach the roots.

Proper watering technique involves allowing the top inch or two of soil to dry out completely before watering again. When you do water, do so thoroughly until it runs from the drainage holes, then discard any excess from the saucer.

Over time, a healthy pothos will fill its pot with roots, a condition known as being root-bound. Signs of this include roots growing out of the drainage holes, slowed growth, or the plant requiring more frequent watering. When these signs appear, it is time to repot the pothos into a container that is just one to two inches larger in diameter.