Dimensional specifications, pressure classes and engineered jointing for specialized infrastructure service.
Fertigation Equipment
What fertigation is and how a venturi works
Fertigation means giving dissolved fertiliser with the irrigation water so it reaches the roots exactly and less is used. A venturi is the simplest way to do it: water passing its narrow throat drops in pressure and draws fertiliser from a container into the flow.
The venturi is fitted in a bypass with a valve on the main line, before the filter. To stop fertiliser flowing back to the water source, put a check valve in its line, and run plain water through the network for a few minutes after each feed.
How to choose a venturi size
The venturi size should match the flow and pressure of the irrigation line; a larger venturi draws more fertiliser per hour but needs a larger pressure difference to work. Small orchards and greenhouses are well served by the smaller sizes, and large fields use the larger ones.
If the line pressure is not enough to create suction, the venturi will not draw; in that case partly close the valve on the main line so more water passes through the venturi. Set the injection rate with the valve on the suction hose.
Looking after a fertigation system
Dissolve the fertiliser fully and strain the solution so undissolved particles do not block the filter and the drippers. Do not mix different fertilisers unless you know they are compatible, because some combinations precipitate.
After each feed, rinse the venturi and the suction hose with clean water, and take the parts apart and clean them at the end of the season. A plastic venturi is not corroded by fertiliser, but long exposure to direct sunlight shortens its life.
Fertigation Equipment — Frequently Asked Questions
Does a venturi need power?
No; it works on the water pressure difference in the line.
Which venturi sizes are supplied?
From 1/2 to 2 inch.
Where is a venturi fitted?
In a bypass with a valve on the main line, before the filter.
Why does the venturi not draw fertiliser?
Usually the pressure difference across the venturi is too small or the suction path is blocked; partly close the main-line valve and check the suction hose and strainer.
Should the venturi go before or after the filter?
Before the filter, so undissolved fertiliser particles are caught before they reach the drippers.
Can't find what you need?
If you require specific sizes, custom fittings or specifications not listed in the catalog, our technical team is ready to assist and review custom requests.