A system for controlling the depth of at least one closing wheel in an agricultural row unit for planting seeds in a furrow. The row unit includes a firming device that passes the seeds into the soil at the bottom of the furrow, and at least one closing wheel that is pressed into a side of the furrow to close the furrow over the seeds. A control system senses the depth of the closing wheels in the furrow relative to the depth of the firming device, and adjusts the downward pressure on the closing wheel, based on changes in the sensed depth of the closing wheel, to compensate for changes in the hardness of the soil.
