VEGETABLE FORCING UNDER POLYETHYLENE TUNNELS WITH BITUMEN MULCH
The advantages of earlier emergence of seeds in spring can be multiplied if care is taken to protect the young plants against possible adverse climatic conditions. Plastic tunnels provide a good shelter for young plants which were sown or planted and allow the black mulch to perform at his best.
Most experiments are concentrated on the use of quite narrow pands of asphalt mulch in the open, in order to save soil moisture (Lippert et al., 1964) and hasten seed emergence by soil temperature rise. (Takatori F.H. et al., 1964, Hillel, D. 1965). In our experiment we tried to cover the entire base of the plastic tunnels in order to have the soil absorb as much additional solar energy as possible, and to protect the plants by the plastic tunnels.