Spring is fast approaching, looking at the window it may already be here!! And with the lack of rain now is a good time to check out that drip irrigation system and make sure it is ready to go. First of all what is drip irrigation? Drip irrigation is the process of applying water directly to the plant with a slow, steady application of water. Drip irrigation components come in a wide variety of application methods and delivery systems. For our discussion we will focus on a drip system that I have found to be very economical, reliable, and easily maintained. 

First of all lets look at the components of the system starting with the point of connection:

• Point of connection is where we will tie into the main water source. It can be a tap off of the water line or tee-ed off of a hose bib (faucet).  At the point of connection we will have our control valve or on/off valve. For an above ground installation the valve will need be an anti-siphon valve, located above ground and set to a height of 12 inches above the soil. Our control valve could also be a battery timer valve attached directly to the hose bib and the hose bib should have an anti-siphon device hooked to it as well (most new homes have these installed by the builders, older homes will have to add one). It is very important to keep irrigation water separated from the potable water source. 
• Next is one of the most, if not the most, important part of any drip system, the filter. Drip filters come with different screen types and mesh sizes, generally for the home garden a nylon mesh of 200 micro pores is sufficient. This filter should be cleaned at least twice a year, good rule of thumb would be to clean prior to starting up the system in the spring and then again half way through the growing season, some time around July. Make it a celebration event, 4^th of July filter cleaning will be like setting off fireworks for the plants. After cleaning the filter and putting it all back together, turn on the system and make sure you have no leaks. 
  
• Next component is the drip regulator. Water pressure regulation is important. Most homes have an incoming water pressure in excess of 50 PSI, you will want your regulator to lower the pressure to 30 PSI. 
• After the regulator we hook up the drip lines. This is usually done with a .710 drip line (irrigation experts generally call this ½ inside diameter tubing for simplicity). Off of our drip line we install the various components of the drip system. These call be low volume micro-spray units or drip emitters that range from (.5) ½ gallon per hour up 5 gallons per hour. I have found that the one gallon per hour emitter generally does a great job if it is installed properly and we regulate the time we water correctly. Installing the drip emitter should be on the up-hill side of the plant, for new plants that's right beside the root ball for established plants it would be at the drip line. 

Drip irrigation maintenance is the key to a successful system and live plants. Turn on the system periodically and “walk” the system to ensure you have no leaks (generally they will show up readily as a stream of water that is hard to miss), make sure those emitters are dripping and not clogged up. And most important clean those filters.  Dirty filters can cause emitters to clog and they can impede the amount of water running through the system.

Want to learn more about irrigation? Solano Community College Horticulture Department will be offering Hort 071 Irrigation Principles in the Fall Semester 2015.