Greasing Schedule/Pressure washing

How often do you guys grease your fittings? I seem to get suspension creaks and squeaks far too often. As soon as I grease them up the noises are gone. I find myself having to grease them almost once per week to quiet everything down. I use a pressure washer to clean my atv after almost every ride. Is it normal to have to grease so much or do you think the pressure washing is having an effect?

I ride maybe 25 miles per week.