La Geria is one of the most unique and typical farming scenes of Lanzarote and the whole archipelago. It was born of the need to make the most of the vast expanses of land that were left covered in sand (lapilli) after the volcanic eruptions of Timanfaya.
The island’s farmers came to realise that plants that had been partially covered in volcanic charcoal or sand had a more favourable growth. Thus, the idea was born of digging under this superficial layer, measuring one or two metres, to reach the soil beneath it and plant their crops there.
The holes dug out for this purpose are shaped like small cones and are often sheltered from the wind by a small wall. The unique properties of the lapilli enabled the dry crops to survive in a land with such little rainfall. This is due to the fact that this volcanic material is capable of absorbing and retaining humidity, both from rainfall and from the atmosphere. Furthermore, it helps absorb rainwater by favouring its filtration into the soil and preventing erosion. This form of tephra, locally known as picón, also has insulating properties that prevent water from evaporating and help the temperature of the plant remain stable.