In order to select degradable covering film for mini watermelon under facility cultivation in Beijing
area，this paper took the black plastic mulch，black non-woven film mulch（biodegradable） and silver reflective
cloth（biodegradable） as experimental material，and studied the effect of different covering films on growth
period，growth vigor，root activity，yield and quality of mini watermelon．The results showed that there were no
significant diferences in the effect of these 3 films on watermelon yield．But the female flowers of the plant under
black non-woven mulch blossomed concentrately，and its root activity and fruit quality were better than that by the
other treatments．Moreover，it could be degraded within 6 months．Thus，we suggested to use black non-woven
mulch as covering film in early spring under plastic shed for mini watermelon cultivation in Beijing area．