Researchers at Washington State University are testing solar panels in Northwest orchards to evaluate their effectiveness and economic viability for both power generation and crop protection.

The area is home to about a third of Washington’s 188,000 acres of apple orchards. Neat rows blur into the distance, where Mount Rainier’s foothills rise up to meet a sky that’s almost always blue.

TK Family Farm in Polk County, NC, has found success using precision and high-density growing techniques at its orchard that ...