What Is a Sprinkler Drip Tube?

About Drip Tubes

• The host supply line for drip tubes is usually about 1/2 inch in diameter. This is the main line that carries water to smaller tubes that branch off and distribute water to plants directly at the roots. The smaller lines are usually 1/4 inch in diameter. All drip irrigation tubing is made out of molded, flexible PVC plastic. This material resists corrosion and rust, and is flexible enough to move anywhere water is needed within a garden or lawn.

Connecting Drip Lines

• Drip lines connect at several points to create a drip system. The main supply tube connects to a tubing adapter, which uses compression to hold the line against an adapter with pipe threads. The pipe threads are then connected to a small water filter screen, and then to a pressure regulator, backflow preventer and the water valve itself. The smaller drip lines connect to the main 1/2-inch line by pressing barbed adapters into the main line. These barbs puncture the pipe and connect to a 1/4-inch drip line. These barbs can be installed anywhere along the supply pipe.

Plugging Drip Lines

• Occasionally, you may want to remove or relocate a barb within a main drip line. It's possible to plug these holes with a goof plug. The goof plug has the same diameter opening as a barb, so they fill the hole completely, but the goof plugs do not contain holes on the other side. Instead, they are sealed to prevent leaks. Goof plugs are available at most home improvement stores and usually cost about $1 for a bag of 6 as of the summer of 2011.

Laying Out Drip Lines

• When laying out drip irrigation tubes, it's best to run the main supply line around the perimeter of the garden bed. That way, the smaller lines can be run from any point along the perimeter of the garden. It's also possible to run the supply lines up and down trenches along vegetables. Instead of using 1/4-inch drip lines, you can simply punch a small hole every 2 feet. The holes will allow water to gently flow out of the pipe and into the irrigation trenches.