Abstract: A root-irrigation pipe, including a hollow pipe with holes in two terminals, an inside of said pipe is parted into a first side-chamber and a second side-chamber by a separate-wall extending longitudinally. A sidewall of the first side-chamber opposite said separate-wall has an opening extending lengthwise, the separate-wall distributing perforative orifices uniformly lengthwise; a plurality of blocks distributed lengthwise are slidably located between said first side-chamber and the opening, blocking the orifices, a space between the block and the flank of said first side-chamber forming a seeping-cleft with an edge of the opening.