Automatic solar irrigation kit for plants

Three safety features accompany normal operation. An anti-siphon valve prevents water from flowing back into the pump when it stops, a filter protects the circuit from sediment, and an audible alarm sounds when the reservoir runs dry or the filter becomes blocked. This filter is the only component that requires regular attention, and a dripper delivering less than its neighbours almost always indicates a blocked filter rather than a fault with the dripper itself. Remove it, rinse it under plain water, and refit it without forcing. The audible alarm is triggered by the same two causes, an empty reservoir or a blocked filter, and it is worth checking the latter before concluding it is the former. A completely blocked dripper can be cleared by removing it and blowing through it, which is sufficient in most cases.

The kit is supplied without a reservoir, leaving you free to choose the volume based on how long you'll be away. A 20-litre bucket is sufficient for a weekend away with a few pots, while a 100-litre garden bin or a rainwater collector will last two to three weeks on a well-configured terrace. Place the reservoir in the shade to minimise evaporation and algae growth, keep it covered, and raise it slightly if you want to reduce the strain on the pump. Rainwater works perfectly well, provided you filter out leaves before they enter the reservoir rather than at the pump itself. On a balcony where the reservoir takes up too much space, clay spikes placed in the most demanding pots can take the pressure off the kit by bridging the gap between two watering cycles.

Unroll the line before making any connections, laying it flat in the sun for half an hour so the pipe loses the memory of its coil and sits without twisting. Then work from the reservoir towards the furthest point, inserting a dripper at each pot, cutting the pipe as you go rather than measuring out lengths in advance. Each tee fitting creates a branch, and the order in which you place them makes almost no difference to the flow rate as long as the line does not loop back on itself. Finally, secure the pipe to the ground or along the planter with clips, because a line that shifts will eventually pull a dripper free, and all the water will then flow out at that one point, leaving the rest dry. Check the entire line on the first cycle, dripper by dripper, rather than trusting the installation.

Bring the electronic module and its battery indoors at the first sign of frost: a lithium battery handles prolonged cold poorly and loses capacity permanently if it freezes flat. Empty the pipe and drippers before storing them by lifting the line from one end to the other, as any water left inside a dripper will split it when it freezes. Charge the battery to half capacity before putting it away rather than leaving it empty all winter, and give it a few hours in the sun before the first use in spring. Our article on oyas throughout the season places this kit in context alongside other ways of watering while you're away.