Pressure wash your fence annually to keep it looking like new. You shouldn't have to apply fresh paint or sealant every year, but you should reapply it every few years to keep it protected. It’s important to be careful when pressure washing a wood fence so that you don’t damage it. It’s a good idea to add a tip to the pressure washer that will fan out the water and not put grooves in the fence. A 25-degree tip is a good choice to use that will keep your fence perfect.