Drip irrigation system design for greenhouses and nurseries

Pressure compensating (PC) drippers operate between 7 to 55 PSI and deliver positive results when installed correctly. Using The Drip Store brand name PC drippers with one or four outlets ensures uniform flow rates from each outlet along the length of the drip line. By applying water directly to the pot, the rest of the plant remains dry helping to minimize foliage pathogens, such as Botrytis. Another benefit of drip irrigation is that pesticides applied to the foliage are not washed off reducing the need for spraying. Overall, drip irrigation can help lower production costs based better efficiency, and uniformity aiding in a successful growing season.

To use this category select the dripper flow rate, each dripper will require 1 adapter, pre-cut microtube and a stake.

Step 1: Visualize the area and see your pot layout on the benchs. You may need single or multiple outlets dripper. See the length of microtube that you will need, select from 24" or 36" length. For small hanging baskets you will need to add a weight to balance the dripper.

Step 2: Select the dripper from the product list based on your application requirements, and design features, such as desired flow rate, micro tube length, pot size and pot layout.

For information on how to select and size the polytube laterals, filters and items needed for the initial setup of the system, troubleshooting and maintenance see steps 3 thru 8 below.

Step 3: Sizing the sprinkler lateral lines for your bench length based on the maximum number of heads allowed on each lateral
We strongly recommend polyethylene pipe (poly tubing or blank tubing) for use in the laterals in your layout. Light can penetrate PVC pipe, which can cause algae to grow, leading to many problems, including plugged emitters.

Information you will need to finalize your installation:
Bench length and number of sprinklers, sprayers or foggers allowed on the polytube (see chart for max recommended # of heads allowed on laterals)

Maximum Recommended Drip Line Length with PC Dripper Spacing

Step 4: Sizing the distribution main line
Use the chart below to select the size for your distribution line up to 100 feet, and for your main line up to 125 feet in length. This chart should serve as a general guideline only.

Step 5: Sizing the main control components, such as valves and filters
The components should be sized according to the flow range of the filter. Make sure not to exceed this recommendation.

Step 6: Starting the system for the first time and flushing the system
The most important for you to remember when starting a new system for the first time is to flush the lines. Debris from the irrigation installation can pass into the micro sprinklers and foggers and can cause the irrigation system to plug, or to operate improperly. To properly flush the irrigation system, first connect the valves, filters, and main and distribution pipes. Then flush the line. Second, connect the lateral pipes and then flush the whole system again. Third, attach the micro sprinklers or foggers, open the ends of the laterals and have a final flushing of the whole irrigation system. Close the ends of the laterals one by one before the water is turned off. After complete flushing, check that the irrigation system is operating correctly and adjust if needed.

Step 7: Troubleshooting

• Problem: Flow line broken, filter clogged, micro sprinklers, drippers or foggers clogged or faulty
  • Cause: Pressure too high or too low
  • Solution: Check the poly tubing, clean or replace screen filter, replace or clean micro sprinklers or foggers, check pressure regulator.
• Problem: Micro sprinklers, drippers or foggers have uneven or no flow at the end of the drip line
  • Cause: Too many micro sprinklers on the drip line or too long a run of poly tubing
  • Solution: Make sure that you did not exceed our recommendations.
• Problem: Fittings separating from poly tubing
  • Cause: Fittings improperly installed; compression fitting is not far enough inside the tube, or it is the wrong size fitting.
  • Solution: Make sure you used the correct size color-coded fittings
• Problem: Microsprinklers, drippers, foggers or micro tubing popping out of poly tubing
  • Cause: Pressure regulator is defective, microsprinklers, drippers or foggers are installed improperly, faulty or worn punch
  • Solution: Replace pressure regulator, check or replace micro sprinklers or foggers, plug hole with goof plug, replace or clean punch, or if pressure is too high, install (or replace) pressure regulator
• Problem: Clogged micro sprinklers, drippers or foggers
  • Cause: The use of incorrect filter mesh
  • Solution: The use of a proper filter should avoid clogging problems
• Problem: Microsprinklers, drippers or foggers have calcium deposits (white color buildup)
  • Cause: Hard water
  • Solution: Inject a 1% to 2% chlorine solution through the system
• Problem: Plants appear stressed
  • Cause: Run time is inadequate for the plants
  • Solution: Reset controller for more time

Step 8: Maintenance

• Inspect microsprinklers, foggers, and drippers periodically to insure that none are clogged. It is also important to check the microtubes to see if they are clogged. It is also important to check the microtubes to see if they are out of place.
• Filter screens should be flushed and cleaned at least once a month depending on water quality. Check the filter one week after installation. It should give you an idea of how often to schedule cleaning.
• Tubing lines should also be flushed periodically; again, water quality will determine the frequency of flushing.
• Remove end caps, or open hose ends, to flush the line once a year.