This study reports development of green infrastructure construction method applying plastic rainwater storage structure suitable for load resistance to planting base. Observation items in this study are water level, moisture content, soil temperature, and heat index, and test surveys are soil hardness test, permeability test, and root elongation. As a result of this research, the planting base has a pF value within the range of 1.5 to 2.7, which is an effective value for plant growth. In the control plot, there was a tendency for excessive humidity (pF value: 1.2 to 1.4), and a value outside the effective value for growth was observed. Under the shade of greenery, the daytime temperature is about 3°C lower than the surface of the pavement. In the one year after green infrastructure construction method applying plastic rainwater storage structure to planting base, it was confirmed that Zelkova serrata and Liquidambar styraciflua showed elongation of the root and vigorous rooting of fine roots in both 100% and 50% filling of the planting base soil. This study showed the effectiveness of the green infrastructure construction method that applied rainwater storage structure to the planting base for roadside trees.
