Automating Fertigation with a Zooz LR Z-Wave Relay

Last year I added automated drip irrigation to our vegetable garden along with an EZ-FLO fertilizer injector for fertigation — the only problem being that the injector wasn’t actually automatic. In this video I fix that, making the EZ-FLO truly hands-off with a Zooz LR Z-Wave relay, a 12-volt power supply, and two quarter-inch solenoid valves, all wired into a custom 3D-printed enclosure and controlled through Home Assistant.

What’s Covered

I walk through the whole build: the parts, why normally closed solenoid valves matter for safety, wiring both valves in parallel off the ZEN58 dry contact relay, tidying everything into a printed enclosure with cable glands and lever wire connectors, and installing the valves on the EZ-FLO’s inlet and outlet lines. On the software side, the relay pairs to Home Assistant over Z-Wave JS with SmartStart, giving you a single switch entity to schedule or automate however your garden needs — layering fertigation on top of the moisture- and weather-based watering automation I already run.

Products Used

• EZ-FLO Premium Lawn and Garden Feeder — Inline fertilizer injector that mixes nutrients into your irrigation water.
• Zooz ZEN58 Low Voltage XS Relay — A tiny Z-Wave Long Range dry contact relay (9–40V) that switches both valves.
• Waterproof 120V AC to 12V DC Power Supply — Powers the relay and both valves from one source.
• 1/4” Quick Connect Normally Closed Solenoid Valves — Fail-shut valves for the inlet and outlet lines.
• 2-in, 8-out Lever Wire Connectors — Make the parallel wiring dead simple.
• Customizable 3D-Printed Project Enclosure (MakerWorld) — Sized to fit the relay, power supply, and connectors.

Everything integrates directly with Home Assistant through Z-Wave JS — local, no cloud required.

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