Emitter flow rates
| Emitter type | Flow | Best for |
|---|
| Pressure-compensating dripper | 0.5-2 GPH | Long runs, slopes, uneven elevation - flow stays constant |
|---|
| Standard dripper | 0.5-2 GPH | Short, level runs |
|---|
| Inline drip (emitter tubing) | 0.5-1 GPH per emitter | Bed grids, hedges, groundcover |
|---|
| Micro-sprayer | 5-20 GPH | Widely spaced shrubs, nursery pots |
|---|
Emitters per plant (wet the root zone, not just the stem)
| Plant | Emitters | Weekly water (growing season, rough) |
|---|
| Vegetables / annuals | 1 × 0.5-1 GPH | 1-2 gal |
|---|
| Perennials / small shrubs | 1-2 × 1 GPH | 2-4 gal |
|---|
| Large shrubs | 2-3 × 1-2 GPH | 4-8 gal |
|---|
| Trees | 3-6 × 1-2 GPH, spread at canopy edge | 5-15 gal |
|---|
Do the math for your bed
The Drip Irrigation Calculator turns bed area and plant spacing into plant count, total emitters, zone GPH and run time; the Drip Run Time Calculator converts per-plant gallons into session minutes. Valve capacity rule of thumb: keep each valve's total flow in the 100-300 GPH range.
Frequently Asked Questions
Why spread emitters to the canopy edge on trees?
Absorbing roots live where water drips off leaves, not against the trunk. Concentrating emitters at the stem encourages shallow, vulnerable roots.
Are pressure-compensating emitters worth it?
On any run longer than ~50 ft, on slopes, or with mixed elevation - yes. They hold flow constant despite pressure differences, which keeps the schedule math honest.