ENTERTAINING BACK YARD
LOW-VOLUME IRRIGATION HYDROZONES*
| Zone | Description of Plant Material | Emission Devices |
| 1 | Trees (sparse planting) | Root zone watering systems (with bubblers), adjustable bubblers, or single outlet emitters |
| 2 | Large shrubs (sparse planting) | Adjustable bubblers, single outlet emitters (bug-type), or in-line pressure compensating dripline |
| 3 | Shrubs and perennials (sparse planting) | Single outlet emitters or in-line pressure compensating dripline |
| 4 | Shrubs and perennials (sparse planting) | Single outlet emitters |
| 5 | Lawn | Low-volume, multi-stream rotator sprinklers |
| 6 | Grouped plants - Shrubs, perennials, vine, and ornamental grasses (dense planting) | Multiple outlet emission device with drip emitters (bug-type) or single outlet emitters |
*HYDROZONE
The word “hydrozone” is used to describe the practice of grouping plants that have similar water requirements. Hydrozoning is a key component of a water-efficient irrigation system and landscape. Effective hydrozoning requires an understanding of plants, the rate in which water moves into and through the soil (infiltration rate), soil type and texture, landscape design, irrigation, drainage, slope, sun exposure, and weather conditions.
Hydrozones divide a landscape irrigation system based upon individual plant water requirements, plant height, and planting density. Plant species with similar needs are selected and grouped within each hydrozone. It is also effective to create microclimate zones so that plants with higher water needs are closest to the house and plants with lower water needs are on the perimeter of the garden or landscape.
Each hydrozone will contain plants that will be irrigated on the same schedule, using the same irrigation method. Generally, each hydrozone is served by one valve or control zone (although more than one valve may be required to service an area due to flow and water pressure). By using controllers with multiple run times that are able to support low-volume systems (cycle and soak) and by dividing the landscape into hydrozones, each area will receive the amount of water it needs without puddling or runoff.
The result of hydrozoning is improved plant health and less water use.