Drip irrigation is a watering method that emphasizes the slow, precise application of water. At its core, it’s about reducing water usage by making the watering process more efficient. If a traditional sprinkler system is a shotgun, a drip system is a sniper rifle.
The main component of any drip system is the emitter, commonly called a dripper. The emitter is where the precision, accuracy, and uniformity of a drip system comes from. Emitters are flow control devices that limit how much water they output through a number of different methods. Standard emitters use a series of small passageways to slow incoming water down to the desired rate. These emitters will output the listed amount at 25 psi, with the flow rate changing as the pressure goes up or down. Pressure compensating emitters use a silicone diaphragm to compensate for incoming pressure changes, which means their output doesn’t change with pressure so long as that pressure is between 10 psi and 50 psi.
Drip tubing is another common part of a drip system. This is the black polyethylene tubing you’ll find in hardware stores and backyards across the world. Drip tubing comes in a number of different sizes, with the most common being 1/8”, 1/4", 1/2", and 3/4". The larger sizes (1/2” and 3/4") are used as main lines, and often have drippers inserted directly into them with the help of a specialized hole punch tool. The smaller sizes (1/8” and 1/4") are typically used as sub-lines, extending off of the main line and having an emitter at the end. Smaller lines are sometimes referred to as “spaghetti” tubing.
While drip tubing is the most common way to supply a drip system, PVC works much better in many cannabis-specific applications. PVC pipe can move significantly more water than drip tubing can and its rigid nature prevents kinks, which can cause issues with drip tubing. Many of our clients use PVC-based drip systems to great effect. Drip manifolds – or octopus heads, as they are often called – are ideal for dense indoor applications and tiered growing systems, and hook up to PVC via threaded connections.
There are dozens of ways to irrigate your plants, but few have as many benefits as drip irrigation. A drip system lets you to predict exactly the amount of water and nutrients each plant will receive over a given amount of time, allowing you to budget for those items more accurately. Drip systems also allow granular control via valves and timers.