I have used drip irrigation and micro-sprinklers for more than 30 years. I know their limitations as well as their advantages. It is time for drip irrigation or micro-sprinklers — in fact, it is becoming the mandatory method for watering plants.
The hardest part of drip irrigation is allowing the system to run long enough. Where bubblers may only need to run for a few minutes, drip needs to run for hours. If you use one gallon per minute bubblers and are running them for 10 minutes, your one-gallon-per-hour drip emitters would need to run for 10 hours to supply the same amount of water. I use larger emitters and several emitters on large plants to cut back the time, but it is still hours to irrigate my plants using drip.
Determining the run time depends on the type and size of the plants you are watering. But for most newly planted plants, it is usually a couple of hours, where an old large established plant may need to have the water on for five or six hours. That may seem like a long time, but you may have to water that old established plant only once a week to once a month.
A drip irrigation system has some limitations. First, drip irrigation hose lasts only about five years if left out in the sun. If you bury your hose it can last much longer. The worst problem with drip irrigation is that you place water in only one spot in the soil. This can mean that all your plant’s roots are growing in one spot in the soil. If this occurs your plant can die if that spot dries out. Or if the roots are in a confined area a tree is more likely to blow over because the roots have not spread out over
a large area.
An answer to this problem is to place several emitters by each tree and to move the emitters out, as the plants grow larger.
Drip irrigation is old technology; its limitation has been recognized and solved. Today I use mirco-sprinklers. Micro-sprinklers are a newer type of drip irrigation that, instead of dripping water in one location, act like small lawn sprinklers and will spray water over an area
of the ground.
Micro-sprinklers spray water at 10 to 20 gallons of water per hour compared to a lawn, which sprinkler sprays water at three to five gallons per minute (1800-300 gallons per hour). Micro-sprinklers are not meant to replace lawn sprinklers. Micro-sprinklers are to apply water to planters over a larger aream allowing the plant’s roots to spread out and becoming
For fruit trees, I place a half spray micro-sprinkler on each side of the tree spraying away from the tree. This allows the tree roots to grow outward and keeps water off the truck.
The emitters should be placed at the drip line of a tree or shrub. The drip line is the edge of the shrub or tree where rainwater drips off the plant. As the tree grows larger, the drip line becomes farther and farther away from the point where emitters were first placed. Now you need to move the emitters out to match.
With micro-sprinklers we can increase the water pressure and make the sprinklers spray farther to match the drip line.