Red Plastic Mulch
For Tomatoes, Strawberries, Melons
Grown naturally they would be receiving red light waves from ripening tomatoes - receiving these 'signals' earlier they are mobilized into ripening and producing more fruit at break neck speed - which is what nature has programmed them to do.
Eggplants also respond better to the use of Red Plastic Mulch, not as much as their Solanaceous cousins the Tomato and pepper clans, they only show a 12% increase in yield at best, as opposed to 20% for Tomatoes. Peppers as per a Penn State Study did not show any dramatic increase when grown with Red Plastic Mulch, however - they responded favorably to silver mulch when compared to black with an average 20% increase in fruit yield and size.
Red Plastic Mulch is not only beneficial in tomato production, it has also been proven highly effective in increasing strawberry yields. "Yields over the red plastic (SRM-Red) were compared with those over standard black plastic in field experiments at a research center and on a commercial strawberry farm. Yield per plant and size per berry were greater over the red than over the black plastic at both locations." See - Strawberry Yield over Red versus Black Plastic Mulch American Society of Agronomy
Red Plastic Mulch has also been shown to be the best for Melons. See: Influence of Preharvest Factors in Melon Fruit Quality
Cantaloupe and closely related musk type melons are an exception - Red Mulch does not appear to have the same effect on them - however "this crop appears to respond more to green IRT or dark blue mulch compared to black with an average 35% increase in marketable fruit .... Lowest yield of marketable cantaloupe were harvested from plants grown on either white or black mulch at this location. Summary and Recommendations for the Use of Mulch Color in Vegetable Production Penn State Extension.
Red plastic mulch has the added benefit of preventing and at times eradicating root nematodes, an occasional garden menace. "Red plastic mulch is the best way to combat root knot nematodes. Results of experiments indicate that tomato plants grown with red plastic mulch were able to ward off nematodes and produce more tomatoes than plants grown with black plastic " See - Colored Mulch Starves Nematodes Gale Academic
One of the disadvantages to using plastic mulch, not just red, but any plastic mulch is that water will pool on the plastics surface. It does penetrate - but very slowly. I have at time poked small holes in the mulch to allow the water to penetrate more readily, but this of course can be time consuming. A drip system under the mulch would solve this problem. Some plastic mulch offered to Home Gardeners has micro perforations which solves the issue also.