Retired schoolteacher Ali Garci wanders among tiny sandy plots, inspecting his potatoes, lettuces and onions.
"It's not land that we cultivate for the profit it brings, but for the art and the pleasure," says the 61-year-old, who works around a hectare (2.5 acres) inherited from his family.
Local farmers have used the "ramli" technique since the 17th century, when Muslims and Jews settled in North Africa after fleeing the Catholic reconquest of Andalusia.
Some found safety in Ghar El Melh, a small fishing town in Tunisia's north.
But they had to battle a lack of cultivated land and water.
They learned to take advantage of the light, sandy soil, and the fact that underground freshwater, which is lighter than seawater, "floats" above the saltier groundwater below.
When rainwater from the hills reaches the sandy area around Ghar El Melh's lagoons, instead of mixing immediately with the brine below, it forms a thin layer of fresh groundwater.
Twice a day, the tides of the nearby Mediterranean raise the level of both, bringing precious freshwater in contact with the vegetables in the ramli plots.
"It's as if the sea is suckling its young," said Abdelkarim Gabarou, who has worked the traditional plots for more than 40 years.
Tunisian farmers in the small fishing town of Ghar El Melh are fighting to preserve a unique way of growing crops on sandy plots using a traditional, delicate irrigation system
Tunisian farmers have learned to take advantage of the light, sandy soil and the fact that underground freshwater floats above the saltier, heavier groundwater below providing crucial water for crops
Retired Tunisian school teacher Ali Garci farms a plot of land inherited from his family and says this traditional form of agriculture recognised by the UN as a globally important heritage is 'totally dependant on rainwater'