Agriculture consists of filling in the space with plants and keeping the right conditions for them to grow. There are limiting factors that must be pondered before deciding how to do that. Modern technologies allow high density orchards, which maximise yield per hectare. However, this is neither the case of dry farming nor the case of extensive production which does not rely on chemical fertilisers.
Today, the common spacing in Spain for new almond and olives orchards is 7 metres x 7 metres, which translates into 204 trees per hectare. This density is used regardless the orchard is irrigated or not. Rainfall in La Mancha varies from 200 to 500 millimetres per year. 600 mm is considered the right rainfall for almonds to yield properly, so I chose a spacing that provides at least an extra 50% rainfall per tree. The final spacing: 9 m x 9 m, or 123 trees per hectare. This distance increases nutrient availability, while harvest, pruning and treatment costs are reduced.
The plot shows in green the almond trees in this field of 1.3 hectares. They were planted in 2013. All orchards I set up afterwards follow the same pattern.