This is how vineyards grow on Canary Island in Lanzarote where there is no irrigation system and very little rainfall, with strong winds. The small island has more than 300 volcanoes and therefore the place is mixed with a lot of ash. Grape saplings are planted specifically in dug pits or, alternatively, a rock wall is placed around the sapling. This is done to make it easier for the roots to reach the fertile soil layer and to maintain the moisture of the grapes. This system works well considering that there is very little rainfall, no artificial irrigation, the plants are fed from the dew, that is concrentraed in the walls of the cones around it.