The outdoor unit dumps house heat into the yard. If the yard dumps itself back onto the coil, capacity falls and the compressor lives a shorter life.
Clearance
About two feet on the sides. The top needs to throw air — do not deck over it or store plywood on the fan guard. Shrubs look nice in March and choke the coil in June. Cottonwood in this county will felt a condenser in a week.
What you can do
Power off. Pull toys, bags, and weeds back. A gentle garden hose from the outside in, not a pressure washer. You are rinsing lint, not stripping paint. Bent fins are lost surface area. A screwdriver is not a fin comb.
If the coil is still matted after a rinse, that is a chemical clean on a visit — not a second pass with the car-wash wand.
What you should not do
Do not open the electrical panel. Do not “spin the fan with a stick to see if it helps.” Do not run it with the disconnect pulled “to rest it.”
Blocked condenser is one of the few summer problems that is actually your landscaping. The Toolbox asks. Book if it is clean, running, and still warm inside.