Root Watering Systems Save Water

What are root watering systems? It is a water-efficient sub-surface irrigation system for tree and shrub roots. The RWS (root watering system) units are placed underground (usually 2-3), delivering water straight to the roots. The water seeps out through the unit’s holes and causes the roots to grow downward (decreases root intrusion). Because of its vertical design, it waters the entire root system, those near the surface and deep underground. Once the watering is complete, the check valve prevents system backflow.

Root Watering System Overhead


There are many benefits to implementing a root watering system for your trees and shrubs. It eliminates the difficulty of irrigating compacted soils (clay) because it bypasses above-ground water penetration and diminishes runoff.

The system uses sub-surface, low-emitting bubblers which minimize evaporation, and erosion. This makes it a highly efficient system because water is placed only where it is needed and can be absorbed.

Another advantage of irrigating directly to the roots is it produces fast, healthy tree growth. With a strong root system, your trees will have more stability in high winds, protecting it from damage.

Landscape aesthetics are greatly improved with the reduction of above-ground irrigation equipment. Not only does it look cleaner, but it allows the landscape architect to design more freely without the concern of walking hazards and disruption of hardscapes.



  • Root watering systems are available in three different sizes:
    • 36” for large and small trees
    • 18” for small trees and large bushes
    • 10” for small bushes and shrubbery
  • They are constructed with a rough plastic mesh which has more than 14,000 holes for delivering:
    • Water, air, and nutrients to grow healthy roots
  • Vandal resistant grates
  • Some models include a swing pipe for easy, fast connection to lateral water lines
  • Check valves/bubblers are pre-installed on most models
  • Some brands are compatible with drip line and emitters

Tips for Using a Root Watering System

Here are a few tips for installing and using a root watering system for your landscape.

  • Install an RWS on a separate zone because the watering needs for your trees will be different
  • In order to strengthen and aid in even water distribution, you can fill your system filter with gravel
  • Ensure there is even space between RWS units
  • Number of RWS units used:
    • 2-3 units per large tree or shrub is recommended
    • 1-2 units per small shrub is recommended
  • When installing a transplanted tree:
    • Make the hole bigger than the root ball + enough space for root growth
    • RWS units should be placed outside the root ball
  • When installing a new tree:
    • For the first few weeks of growth, you can use above ground irrigation to ensure proper watering
    • Afterwards, the overhead irrigation can be moved further out for a few more weeks
    • Then it should finally be dependent on the RWS units