Heirloom tomato varieties continue to be popular among home gardeners. To get the highest production from tomatoes, some growers have been advocating the use of plastic mulch. New research in Ohio suggests that growing tomatoes in organic mulch may be even better.
Researchers at Ohio State University grew the heirloom tomato variety 'Nebraska Wedding' with various mulches to compare production and growth. They used five different planting treatments: bare soil, black plastic mulch, shredded newspaper mulch, wheat straw mulch, and composted landscape bark mulch. The organic mulch was applied to a depth of 4 inches. One half of the plots had herbicide and fungicide treatments, and the rest did not.
The highest yields were achieved on the plots with shredded newspaper mulch, regardless of the pesticide treatment. While the newspaper mulch resulted in the lowest soil temperatures, it suppressed weed growth better than any other organic mulch. Even though the soil under the black plastic mulch reached the highest temperature, the plants had lower yields than all of the organic mulch treatments, regardless of whether pesticides were used or not. The newer red plastic mulch was not trialed in this experiment. Home gardeners may want to experiment with growing tomatoes in newspaper mulch next summer, and even do their own comparisons with red plastic mulch.
For more information about this research, go to: Ohio State University.