The matching of a specific vegetable to a specific-colored plastic mulch is continuing. The different colors "fool" the plants into thinking they have more competition from other plants than they actually do, which makes them produce better. Recent research has matched tomato and strawberries with red mulch, peppers with silver mulch, summer squash and cucumbers with blue mulch, and melons with green mulch. Now herbs are getting into the act.
Researchers at the USDA Agricultural Research Service grew basil using mulches in six different colors. The leaves of plants mulched with red plastic were larger and more succulent, and had a greater fresh weight than those plants grown in black mulch. Basil plants grown in yellow and green mulch produced significantly higher concentrations of aromatic compounds than those grown in white and blue mulches.
For more on this colored plastic mulch research, go to: Agricultural Research Service Web page at www.ars.usda.gov/is/AR/archive/sep03/mulch0903.htm