The sky opened up and poured for an hour. In that 60 minute span a measured 1 inch of precipitation recorded.

The lawn was well soaked. Baseline moisture content before was 43% and by the end of the drenching it had risen to 85% where it peaked.

Heavy rain having ended, the moisture plot on the chart begins a steep descent. Over the course of 3 hours following the storm the moisture level begins to stabilize. The last data point in the chart is very quickly back down to 46%.

Soil moisture retention refers to a soil’s capacity to hold water and make it available to plants over time, which is crucial for healthy plant growth and reducing the need for frequent watering.

Analysis: The soil was already saturated before the event. The added rain rapidly percolated through soil (gravity) and the [type: sandy] soil was unable to retain the excess. Witness the plunge in the graph. The graph demonstrates that there is an ever broadening plateau that forms.

Takeaway: When the lawn sprinklers are turned on during dry spells, any irrigation above 40-45% is wasted water. The soil can’t hold it. Mileage may vary depending on soil type.