Watering Trees and Shrubs with Bubblers

Traditional sprinkler systems can utilize bubblers to deliver a localized, low- pressure flow of water directly to the rootball of trees or shrubs. For bubblers to be an effective watering method, your irrigation system must have the trees isolated on their own dedicated zone. This means bubblers shouldn't activate simultaneously with rotary sprinklers in the lawn or sprinklers in flower beds. Ideally, irrigation systems should be designed with separate zones for lawns, flower beds, and trees, as their watering frequencies and water volume requirements can differ significantly.

If your sprinkler system has bubblers on trees but they are not on an isolated zone, we recommend replacing those bubblers with caps to discontinue their use. This prevents trees from being overwatered when that zone runs. In such cases, trees should be watered manually using an ArborRain Hydration System, Drip Irrigation System, Garden Hose, or Tree Gators.

Choosing the Right Bubbler

Several types of bubblers are available: Adjustable Flow Rate, Pressure Compensating (Fixed Flow Rate), and Micro Bubblers (often associated with drip irrigation systems).

Adjustable flow rate bubblers offer the most flexibility. Their flow can be varied to accommodate different tree sizes on the same zone, slowed down if you notice water runoff from the rootball, or adjusted when individual trees require more or less water than others.

Achieving Optimal Flow Rates

Regardless of the bubbler type, determining the correct flow rate is crucial. We advocate for these slower flow rates to ensure there's no runoff, meaning all the water is absorbed by the rootball. Generally, when flow rates exceed 1 GPM, water tends to run off the rootball, and any water that runs off doesn't contribute to effective watering. If you observe any runoff, reduce the flow rate until it's eliminated. Our flow rate calculator can help you verify that your trees are being watered for the correct duration and receiving the appropriate amount of water each time.

Traditional Sprinkler System Bubbler

Rainbird Micro Drip Bubbler