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Black plastic is fine forBlack plastic is fine for heat-loving melons, and will cut down on the weeds. You would need to make sure that the plants get enough water, though, as this material is not water permeable. In very high heat, though, it might cause plant damage. If temperatures are above 90F, add shade cloth over the plants or add straw over the black plastic to keep the surface temperature cooler. Remove once air temperatures cool.   See:

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