A quick coupling for the flexible tube supplying seeds from a storage bin to row crop units in a row crop seed planter. The quick coupling has an outer annular element with a bayonet connection and a central bore which receives an annular insert having two arcuate sections and holding the flexible tube in place through barbs. The inserts are removable from the outer annular coupling by means of a detent at which point the arcuate sections may be easily removed from the flexible tube.