To provide a functional bag for a plant having the double bottoms in which the purchaser has flowers or seedlings planted, takes the bag back home and can grow them and can receive the excessive water flowing out of the bag after watering and can automatically feed water to the plant even during its absence.

The main body of the bag is constituted with the front side sheet (1a) and the back side sheet (1b) and at least the bottom among the bottom and both sides are made gusseted to form a vertically standing bag (1). The main bottom (B1) is constituted with the bottom sheet (1c) and the intermediate bottom (B2) is formed with the intermediate bottom sheet (1d) Whereby the space between the intermediate bottom (B2) and the main bottom forms the first room (R2), while the upper space on the intermediate bottom (B2) forms the second room (R2). Finally, a water-absorbing material (2) is fixed in the range from the first chamber (R1) to the second chamber (R2) so that the material may work as a water channel.