How to install drip irrigation in raised beds
Measure the bed, sketch the planted rows and put the supply line where it can feed each row. Run a short watering test to see how far water spreads before adding more lines.
Parts for a 4 × 8 ft bed with two straight rows
- 16 ft of emitting line
- Cut two 8 ft laterals, one per planted row.
- Two starts and two flush ends
- Use fittings that match the line. Keep each end accessible.
- A header across the short side
- Run the solid header across the row starts and measure the supply line back to the tap.
Draw the bed and count the parts
Mark the bed dimensions, each planted row and the nearest side to the supply. Count one row-start fitting and one flush end for each lateral.
If a second bed will run at the same time, include all its laterals in the flow estimate. Plan a shutoff for each bed if you want to water them independently. Keep the supply and dripline sizes in your parts list so you can match the fittings.
Assemble the tap connection and the rows
Follow the component instructions and local requirements for backflow protection. Install the filter and regulator appropriate for the selected line. Connect the solid tubing to the head of the bed, then use the specified adapters to start each lateral.
Leave the ends open while flushing assembly debris. Close the ends, run the zone and check the row starts for leaks. Lay out surface tape according to the maker’s outlet orientation instructions.
Check the wetted width at root depth
After a test run, dig a small inspection hole between two outlets and another beside the row. If the soil between outlets stays dry at root depth, closer outlets, a different run time or a second lateral may suit the planting. Recalculate total flow if you add a line.
For a densely seeded bed, inspect the entire planting strip before assuming two lines will cover it. For individually spaced plants in a mixed bed, point emitters can put water at the plants you choose.
Look up the specifications for your drip tape or calculate flow for your rows.
Calculate how long to run your drip irrigation once you know your zone flow.
Sources
- University of Maryland Extension, Drip IrrigationComponents and garden starter kits · Web edition · checked
- Penn State Extension, Drip Irrigation for Vegetable ProductionTape selection, filtration, pressure regulation and maintenance · Web edition · checked
- Colorado State University Extension, Irrigation Run Times with Drip TapeDrip tape specifications and flow units · Web edition · checked