Tropicana: Trying to Make a Greener Orange Juice

Correction Appended: March 12, 2010

How green is your orange juice? A couple of years ago, PepsiCo, which owns the orange-juice brand Tropicana, tried to size up the carbon footprint of the popular morning tonic. It found that each half-gallon carton of OJ is responsible for 3.75 lb. of CO₂.

What was particularly surprising was where much of that CO₂ was coming from. The single biggest contributor to Tropicana's carbon footprint wasn't the transport of the juice to stores or the energy required to operate a modern citrus farm. Rather, it was the fertilizer used...