1/4-inch drip tubing and dripline

What it is

Quarter-inch tubing comes two ways: blank micro tubing, which carries water to a separate emitter, and dripline, which has emitters built in at a fixed spacing. Raised bed kits such as Rain Bird’s lay dripline in rows. DIG’s Microline, for example, comes with emitters every 6, 9 or 12 inches on tubing .170 inch inside by .250 inch outside.

How long one run can be

Each maker limits the length of a single run so the far end still gets water. DIG gives 16, 22 and 28 feet for its Microline at 6, 9 and 12 inch spacing at 25 psi. Raindrip gives 50 feet as the maximum run for its ¼-inch tubing. Rain Bird says ¼-inch blank tubing running from the main line to an emitter should be no longer than 5 feet. Check your own dripline maker’s figure; the drip parts calculator flags rows longer than DIG’s limits.

Emitter spacing and flow

Pressure-compensating emitters keep a steady flow across their pressure range, Netafim explains; non-compensating ones do not. Raindrip notes that with its non-compensating dripline, flow varies with the length of tubing and with elevation, higher near the source.

When it isn’t working

Some plants soaked, others dry. Check the flow at each emitter, Rain Bird says, then take out drippers where there are too many or swap one for a lower flow, such as a red 2.0 gallon-per-hour dripper for a black 1.0. Pressure-compensating emitters keep the flow even when the pressure varies along the line.

A cut or chewed section. Cut it out and join new tubing with barbed couplings or barbed tees.

In the kits we cover

The Rain Bird GARDENKIT includes 35 feet of ¼-inch emitter tubing with 70 pressure-compensating emitters every 6 inches. The Epic kits use drip tape instead, eight tapes of up to 10 feet each. Plan rows and lengths with the drip parts calculator.