Watering globes, crafted from decorative glass or functional plastic, represent a self-watering system designed to provide plants with a slow, continuous release of moisture. They help maintain a consistent soil moisture level, which is beneficial for plants that suffer when their substrate dries out quickly. These devices function on a simple principle: as the surrounding soil begins to dry, air enters the globe’s spout, releasing a measured amount of water into the soil. Determining exactly how many globes a plant needs depends on several variables.
Calculating the Right Number
The physical size of the plant’s container is the primary factor for determining the number of watering globes, as this relates directly to the volume of soil that needs hydration. For plants housed in smaller pots, approximately six inches in diameter, a single small globe is adequate, holding about one cup (250 milliliters) of water. This capacity is sufficient to sustain the plant for about a week under average indoor conditions.
For medium-sized pots, eight to ten inches, a gardener might choose one larger globe or utilize two smaller capacity globes placed on opposite sides of the root ball. Larger globes can hold enough water to last up to two weeks, reducing the frequency of refilling. Containers twelve inches or larger, especially those holding substantial foliage, require a minimum of two large globes to ensure even moisture distribution across the entire root system.
Variables That Change Water Needs
The baseline calculation based on pot size must be adjusted by three factors that influence a plant’s water consumption rate. The first is the plant species itself, as water requirements vary dramatically. Plants that thrive in continuously moist soil, such as ferns or tropical foliage, have a higher demand and may require more globes or larger capacity globes. Conversely, drought-tolerant species like succulents and cacti prefer a dry period between waterings, making watering globes unsuitable for their care, as continuous moisture can lead to root rot.
Environmental conditions also play a role in determining how quickly a globe empties. High ambient temperatures, low humidity, or direct sunlight accelerate the rate of transpiration and evaporation from the soil surface. These demanding conditions cause the globe to release its contents faster. A plant that needs one globe in a shaded, humid room might require two globes, or a globe with a larger reservoir, when placed near a sunny window or outdoors during a heatwave.
The third factor is the material of the planting container, which affects how moisture is retained or lost. Porous materials like unglazed terracotta wick water away from the soil through their walls, increasing the rate of moisture loss compared to non-porous containers. Plastic or glazed ceramic pots hold water more efficiently, meaning the globe’s water supply will last longer. Soil composition is also important; loose, sandy mixes drain faster than dense, loamy soil, causing the globe to release its water more quickly.
Installation and Monitoring Techniques
Installation
Proper installation ensures the globe functions correctly and releases water steadily without clogging. Before inserting the globe, fill the pot with water first, ensuring the soil is moist to prevent the globe from rapidly emptying upon insertion. To protect the stem and prevent soil from blocking the opening, use a pencil or chopstick to create a pilot hole before placing the globe. Insert the stem gently into the prepared hole, aiming for the edge of the root zone. Positioning the globe too close to the main stem risks damaging the plant.
Monitoring
Successful use relies on diligent monitoring and adjustment. Gardeners must regularly check the water level visible in the globe and the soil moisture adjacent to the insertion point. If the globe empties in just a few days, the plant likely needs a larger globe capacity or an additional globe. It is helpful to conduct a trial run a few weeks before relying on the system for extended periods to establish an accurate refilling schedule specific to the plant and its environment.