Abstract: A valve-automatic-pilot couples to electrovalves that control a watering cycle.The automatic-pilot includes a U-shaped magnetic circuit having two vertically spaced, parallel, and horizontally extending legs. The upper leg of the magnetic circuit carries a permanent magnet. An electrical coil is mounted between the two legs of the magnet circuit with a bottom of the coil abutting the lower leg of the magnetic circuit, with the top of the coil spaced from the top leg of the magnetic circuit, and with an open central axis of the coil extending vertically. A vertically movable retaining block is internal of the coil and is spring biased downward to a valve-closed position. When the block is in its valve-closed and first bistable position, a large air gap prevents the magnet from moving the block upward to its valve-open position. A momentary pulse of coil-current of one polarity moves the block upward to its valve-open and second bistable position.