Agricultural machine with variable pressure product distribution system

A product-on-demand delivery system for agricultural product overcomes the problem of over pressuring near application units in order to achieve sufficient pressure to feed further application units. The invention provides two or more main hoppers, each hopper pressurized to a different level by a fan that charges the air nozzles on the hoppers. The near row application units have product delivery hoses that are coupled to a first hopper. The far row application units have longer product delivery hoses that are coupled to a second hopper. The fan charging the second hopper is configured to pressurize the second hopper to a higher pressure than the pressure of the first hopper. The invention provides separate product-on-demand delivery systems to better control the product flow to the row application units on the machine. A product-on-demand delivery system is also provided that can dispense two different products from two main hoppers operated at different pressures.