The outdoor condenser coil of your air conditioner performs a tough job in warm weather. It takes the concentrated heat collected from your home and dumps it into the hot outdoor air. To get rid of the collected heat, your outdoor condenser coil has to move a lot of air. If the coil is dirty or if plants or other objects are too close to the conditioner unit, the fan in the outdoor coil can't move as much air as required for good performance and efficiency. This raises your electricity cost for air conditioning and may shorten the life of the outdoor condensing unit.
Around the outdoor condensing unit of the air conditioner, remove plants and other debris from within 3 feet of the unit in all directions. Make sure the air's upward path in leaving the unit is unrestricted for at least 5 feet. If your outdoor unit is installed under a deck or if someone built a trellis or some other structure above it, either move that structure or hire an air-conditioning contractor to move the outdoor unit.
Most condenser coils are loaded with pollen and dust even when you can't see it. The longest a condenser should go without cleaning is 2 years, depending on how much it operates during the summer. If your cooling season is 4 months or more, annual cleaning is an excellent idea.