The hydraulic system is one of the features that puts the John Deere 445 and its siblings, the 425 and 455, in a completely different category when compared with most other lawn and garden tractors. Hydraulics pack a tremendous amount of power into levers you can control with your fingertips. The standard hydraulic system has two pairs of connection ports under the operator's left foot rest.
Attach the front quick hitch and whichever hydraulic implement you are planning to use--front blade, snow blower, snow thrower or rotary broom.
Examine your quick hitch to determine whether it has single or dual controls. Single control models have no central swivel and only one pair of hydraulic hoses. Dual control models have a swivel that allows the implement to pivot right and left, a hydraulic cylinder that controls the pivot and two pairs of hydraulic hoses.
Connect the hydraulic hoses from the front blade to the hydraulic valve ports by pushing the collar back on the valve ports and pushing the hose fittings into the ports. On a single control model, the lines connect to the two lower ports. On dual control models, the lines from the elevation cylinder connect to the two lower ports, and the lines from the swivel cylinder connect to the two upper ports.
Test the function. The upper lever on the right side of the steering wheel should pivot the implement right and left if the front quick hitch has the swivel cylinder. The lower lever should raise and lower the implement. Pushing the lower lever forward until it locks should put the elevation cylinder into "float" mode, where the implement will generally follow the contours of the ground. If the implement works, but the movements are backward from what you expect, reverse the hoses right and left; never up and down. The upper pair is one circuit and the lower pair is one circuit. If the pivot goes left when you push the lever to the right, swap the two upper hoses right to left. Pulling the lower lever toward the operator should raise the implement. If it lowers it, swap the two lower hoses right to left.