In this article:

• Drip System Tubing
• Drip System Fittings
• Drip Emitter Information Chart

A buyer’s guide to drip watering system tubing, fittings, and emitters— including a handy chart on proper emitter placement.

 
A drip irrigation system uses flexible polyethylene tubing to direct flow to emitters or small sprayers that gradually water a plant’s roots. Polyethylene tubing is used because it is resistant to UV damage and because fittings are easily attached to it. 

Drip hose is commonly used to carry water from the control valve to the areas being watered. PVC sprinkler pipe is used to deliver water from the supply to the control valve since drip tubing won’t hold up under the pressure of constant water delivery.

Drip tubing is made from black polyethylene, which stands up to the sun’s UV rays and therefore can last from 15 to 25 years. Extremely flexible, it winds easily around shrubs and trees, vegetable gardens and flowerbeds. It is usually found in 1/2- or 3/8-inch diameters, so be sure to check the manufacturer’s specifications for both inside and outside dimensions as one brand of tubing may not work with a different brand of fitting.

Half-inch tubing is usually used as the main drip line and can handle flow up to 320 gallons per hour (gph). Narrower 3/8-inch tubing can be used where the system branches off to individual areas; it can deliver up to 100 gph.

The even narrower 1/4-inch micro-tubing is sometimes used to connect emitters. Although 1/8-inch tubing is available, it clogs easily. Micro-tubing can carry about 15 gph and is made of polyethylene or vinyl. Emitters can either be installed into the tubing, or you can purchase the popular emitter line—tubing with built-in emitters.

Lay drip tubing directly on the ground, but don’t bury it beneath the soil where it will be vulnerable to gophers and moles. You can cover it with mulch if you like, but its dark color usually keeps it fairly unnoticeable.

Drip System Fittings

It’s important to use the right size drip fitting for your tubing so the assembly won’t burst apart when the water is on. Different sizes come in different colors—red for 3/8 inch and blue or green for 1/2 inch.

Be aware that these two 1/2-inch fittings are not actually the same size, nor are they interchangeable, so choose one or the other based on the needs of your system.

Couplings extend a drip system by joining pieces of tubing, or they can be used to reattach damaged pipes. Elbows make neat turns around flowerbeds or walkways, and adapters attach drip tubing to PVC pipe.

Barbed, locking, and compression fittings simply snap into drip hose. All three come in sizes for 1/2- and 3/8-inch tubing; 1/4-inch tubing takes barbed fittings. Locking fittings require no force at all to attach.