Over the last six millennia, the once green Sahara has dried out and become the desert we know today. In the hyper-arid Central Sahara, mountain ranges provided and still provide favorable habitats for humans, animals, and plants, in which they have evolved and adapted to the extreme environmental and climatic conditions. It is possible that such mountain ranges, like the Tibesti, were also centers from which Neolithic cultural elements had spread. Some oases in these mountains are home to an ancient tradition of growing useful plants, including date palm cultivation and horticulture. Horticulture gave rise to local vegetable varieties that cope particularly well with heat, drought, and probably also with the relatively high sodium carbonate content in some soils. These varieties have now largely disappeared, as fruits and vegetables are today mostly grown from hybrid seeds found on the global market. Such hybrid plants are more susceptible to pests and diseases under the extreme environmental conditions of the Central Sahara, “requiring” the use of pesticides and sometimes artificial fertilizers. Many gardeners have adjusted to working with seeds from the global market. Others continue to save seeds from the few older varieties they can still gather, or use those of resilient vegetable and fruit varieties from biodynamic cultivation that have been cultivated within the framework of projects. These diverse approaches offer an ideal field for researching how plants are adapted by people to grow in extreme climates. Using different crop varieties as examples, we will, together with the gardeners as citizen scientists, ethnographically investigate local strategies of selection, crossbreeding, evaluation, and seed-saving in the hyper-arid environments of the Central Sahara. The obtained findings from the present can contribute to a better understanding of processes in the millennia-old history of the domestication of agricultural plants.