A spray nozzle assembly includes a pressure dependent variable spray orifice and an internal chamber which is at least partially bound by a flexibly deformable sidewall. At its distal end, the sidewall terminates at a distal face defining the spray orifice extending therethrough. A metering member extends distally from the internal chamber and through at least a portion of the spray orifice. As the pressure of a liquid supplied to the internal chamber by a liquid supply pathway varies, the flexibly deformable sidewall expands or contracts in response thereto. As the sidewall expands and contracts, the distal face moves relative to the metering member to change the effective size of the spray orifice.