A liquid-supplying device configured to supply liquid to at least one plant contained in a pot comprising a substrate (51, 51a, 51b), the liquid-supplying device comprising at least: ∘ A hydraulic conductor configured to convey the liquid by capillary action and comprising at least one first end and at least one second end; ∘ A tube comprising at least one first outlet and at least one second outlet, the second outlet being intended to be in contact with the substrate (51, 51a, 51b), the tube housing at least one part of the hydraulic conductor; The supply device being characterized in that: ▪ the hydraulic conductor forms a loop comprising an elbow and at least a first and a second portion of the hydraulic conductor extending respectively on either side of the elbow, preferably said at least one loop being intended to be placed at least partly in contact with the substrate (51, 51a, 51b); ▪ the loop is arranged outside the tube and at least one portion (13b, 13c) exits through the second outlet of the tube; ▪ the first end and the second end of the hydraulic conductor exit through the first outlet of the tube; ▪ at least one end of the hydraulic conductor among the first end and the second end is intended to be in contact with a source of liquid; ▪ the tube comprises at least one opening (24, 26) configured to allow air circulation between the interior and exterior of the tube, said at least one opening (24, 26) is carried by a side wall of the tube and is arranged between the first outlet and the second outlet of the tube, said at least one opening extends in the form of a longitudinal slot from the second outlet of the tube and towards the first outlet, the diameter of the tube being dimensioned so that, when the hydraulic conductor is housed in the tube and is saturated with liquid, there is a passage in the tube not occupied by the conductor and capable of allowing air to circulate between the first and second outlets of the tube. ∘ A hydraulic conductor configured to convey the liquid by capillary action and comprising at least one first end and at least one second end; ∘ A tube comprising at least one first outlet and at least one second outlet, the second outlet being intended to be in contact with the substrate (51, 51a, 51b), the tube housing at least one part of the hydraulic conductor; ▪ the hydraulic conductor forms a loop comprising an elbow and at least a first and a second portion of the hydraulic conductor extending respectively on either side of the elbow, preferably said at least one loop being intended to be placed at least partly in contact with the substrate (51, 51a, 51b); ▪ the loop is arranged outside the tube and at least one portion (13b, 13c) exits through the second outlet of the tube; ▪ the first end and the second end of the hydraulic conductor exit through the first outlet of the tube; ▪ at least one end of the hydraulic conductor among the first end and the second end is intended to be in contact with a source of liquid; ▪ the tube comprises at least one opening (24, 26) configured to allow air circulation between the interior and exterior of the tube, said at least one opening (24, 26) is carried by a side wall of the tube and is arranged between the first outlet and the second outlet of the tube, said at least one opening extends in the form of a longitudinal slot from the second outlet of the tube and towards the first outlet, the diameter of the tube being dimensioned so that, when the hydraulic conductor is housed in the tube and is saturated with liquid, there is a passage in the tube not occupied by the conductor and capable of allowing air to circulate between the first and second outlets of the tube.