One of the factors of healthy soil is its soil infiltration rate, or how long it takes water to work its way into the soil. Different soil types absorb water at different rates -- sandier soils accept water very easily, clay soils absorb new water slowly and loam soils drain at a near-optimal rate. Compacted soil also affects water absorption, as the particles in compacted soils are jammed together, eliminating some of the air pockets in between. Conduct a simple soil infiltration test to help identify which areas of the yard need aeration or less time under a sprinkler.
Completely clean the inside of an empty 1.36kg. coffee can. Cut the bottom of the can off with a can opener or butcher's knife.
Hold a ruler parallel to the side of the can. Mark the can 3 inches up from the bottom, then mark every inch above that. Number the marks.
Place the can in a dried section of yard. Lay a wooden board over the top of the can. Strike the board with a hammer until the can is driven into the ground to the depth of the initial 3-inch marking.
Pour clean water to the top of the can. Wait 10 minutes, then use the markings on the side of the can to see how much water drained in that time period. Divide the number of inches drained by 10 to determine the rate of soil infiltration per minute.
Repeat in different sections of the yard. Use the information provided by the tests to devise an efficient watering plan for the yard.