A downforce controller (100) has a double-acting hydraulic cylinder (130) that is configured to be coupled to an agricultural row unit (200) and an agricultural toolbar (14) for transmitting a net downforce between said agricultural toolbar and said agricultural row unit. A manifold (110) is coupled to the cylinder (130) and is in fluid communication with a first chamber (134) of the cylinder (130). A pressure control valve (140) is supported by, and in fluid communication with, the manifold (110). The pressure control valve (140) is configured to maintain any one of a continuous range of pressures in the first chamber (134). The manifold (110) includes a counteracting pressure control passage (120) in fluid communication with said second chamber (136).
