Openers for a seeder, configured to be adjustably engaged with a soil surface when in use each opener having compliance to vertical and lateral excessive forces independently applied to soil-engaging parts: a fertiliser tine, a seed tine, a press wheel, a coulter, and a support wheel. The openers share a hydraulic circuit, linked to each internal frame-lifting ram so that localised rise and fall effects arising from soil surface irregularities are shared, maintaining a mean height. The seed tine of each opener is made liftable immediately the preceding fertiliser tine is displaced. The openers do not require external weight support.
