The Pothos plant (Epipremnum aureum), often called Devil’s Ivy, is a popular and resilient houseplant. Originating in the tropical forests of Southeast Asia, this trailing vine is celebrated for its low-maintenance nature. Despite its tough reputation, proper watering remains the greatest source of confusion for new owners. Vague terms in plant guides often lead to accidental overwatering, which is destructive to Pothos. This article clarifies the moisture needs of Epipremnum aureum to ensure healthy growth.
Pothos Preference: Why “Moist” Soil Is Misleading
The common advice to keep soil “moist” is misleading for Pothos, as this implies a constant state of dampness harmful to the root system. Pothos is a drought-tolerant houseplant, better equipped to handle periods of low water than constant saturation. The plant’s thick, waxy leaves store moisture, allowing it to survive dry spells. Its natural environment experiences cycles of heavy monsoon rains followed by dry periods. The ideal condition for an indoor Pothos is to allow the soil to dry out significantly between thorough waterings. Allowing the soil to dry mimics the necessary aeration the roots need. The soil should feel completely dry to the touch before water is reintroduced.
The Danger of Consistent Moisture: Understanding Root Rot
Ignoring the Pothos’ preference for drying out leads directly to root rot, the most common houseplant killer. Roots require oxygen for aerobic respiration, which they draw from air pockets within the soil. When the soil remains saturated, water displaces all the air, leading to anoxic, low-oxygen conditions. In this anaerobic environment, the roots die because they cannot respire. This dead tissue becomes a target for opportunistic pathogens, particularly water molds like Pythium and Phytophthora, which are the agents of rot. The plant displays symptoms above ground, such as yellowing or wilting leaves, despite the soil being wet, because the compromised roots can no longer absorb water or nutrients. If inspected, the roots will appear black, mushy, and may emit a foul odor.
Practical Watering Strategy: The “Dry-Out” Technique
The most effective way to water a Pothos is by employing the “Dry-Out” technique, which relies on testing the soil rather than adhering to a strict calendar schedule.
Finger Test
The simplest method is the Finger Test, where you insert a finger one to two inches deep into the soil. Only water the plant once the soil feels completely dry at this depth.
Weight Test
The Weight Test involves lifting the potted plant to gauge its water content. A fully saturated pot feels heavy, while a dry pot is light, allowing you to quickly determine if watering is needed.
Soak and Drain Method
When it is time to water, pour water slowly over the entire soil surface until it flows freely out of the drainage holes. Immediately empty any excess water from the saucer or cachepot to prevent the roots from sitting in stagnant water.
Environmental Factors That Change Watering Frequency
There is no fixed schedule for watering Pothos, as the rate at which the soil dries out is influenced by environmental variables.
Light Exposure
Light exposure is a factor, since a Pothos placed in bright, indirect light will photosynthesize and transpire more, requiring more frequent water than one in a low-light area.
Season and Growth
The season also plays a role. The plant’s growth slows during the shorter days of winter, necessitating a reduction in watering frequency.
Container Type
The size and material of the container affect moisture retention. A small pot dries faster than a large one, and a porous terra cotta pot wicks moisture away quicker than a plastic pot.
Ambient Humidity
Ambient humidity influences the rate of evaporation from the soil surface and the plant’s leaves. These variables mean the correct watering frequency could range from every few days to once every two weeks, depending on the specific location of the plant.