We have all seen crop plants wilting their leaves when they are under a hot sun. Plants need light (not all plants need the same levels of light) and too much hot sun means less growth. In general, even for crops such as wheat, semi shade means the plants continue full photosynthesis as they don’t have to wilt.
Here at 600 metres up in the mountains in the Ardèche temperatures during July, August and a part of September are usually above 30°celsius and very often in the high 30°’s. Rainfall, apart from the occasional storm is infrequent from April until November.
We use temporary strategies, such as shading covers, whilst the trees planted in the vegetable beds grow and provide shade. Imagine the sky with a light cloud covering giving a diffused light, the vegetation is subjected to less intense sunlight. This type of shade is what we reproduce, in a more dappled way, with the trees.
As ‘every element has more than one funcion’, we have planted fruit and nut trees. Almonds, walnuts (European), mulberries, apples, grapevines and plums. These trees are summer pruned to give a dappled shade.
People often ask whether or not there is competition for resources between the trees and the vegetables. I have been using this type of technique for a long time now and I have never seen any evidence that this is the case. Generally speaking the trees root deeper than the vegetables. The semi shade means that there is less evaporation from the soil which stays damp, under the mulch. This means that the mycelium network is protected and encouraged and able to continue its role in transporting micronutrients and water to where they are needed.
The tree leaf fall and the shredded prunings are left to decompose on the beds. The trees attract birds who leave their droppings behind. It is much more agreable to garden under light shade than in full sun.
One extra advantage is that the plants are, at least in part, protected from late hail storms. These can happen even in July with hailstones the size of small olives. The destructive power such storms is impressive and they have been getting more frequent.