I think you have more rain than us down here Lavanda? We can go for around 5 months without any rain to speak of here. When we visited Extremadura one spring it was just glorious with fields full of wildflowers.
I think we may get more rain but it does depend on areas. The north of Extremadura in the southern shadow of the Gredos Mountains there is more rain and the temperatures are around 5ºC-10ºC cooler. The cherries from the Jerté Valley come from up there. Conversely, in the south of Badajoz province about a one hour drive north of Seville, it is hot as hell in the Summer and much drier but huge areas are planted with vines. When it does rain, in the Summer during a thunderstorm for example, there's total panic because the damp grapes, steamed dry by the sun causes a mildew and has wiped out harvests before now.
I live in the middle of Extremadura and it's an agricultural area. In the 1950s a huge engineering project was constructed by damning the Guadiana River at Orellana and building a canal system that carries water hundreds of kilometres to the 'flat lands' near Don Benito. There, thousands of hectares are irrigated by subsidiary channels of water and the area is given over to rice, maize, tomatoes and thousands of fruit trees. The fruit packing co-operativas employ large numbers of local people during the season who always laugh at the explicit packing instructions for Marks and Spencer — only the best fruit, all the same size in any one pack, all the same colour, etc. etc. but they pay extra for this better quality.
The fruit orchards are planted in rows for easier maintenance and picking. Each tree is irrigated by a time-controlled system linked to the wider water irrigation system. The trees are pruned, checked over and, occasionally sprayed to prevent pests and disease. It's not organic. However, I do know that fruit trees fight pests and other plagues when they are in good health and at optimum strength. That means well-watered. Water is the first line of defence against disease. You mention, Wicksey, that you irrigate, but trees need huge amounts of water to do well and, later, to swell the fruits. How do you irrigate?
Having written that, a local man told us NOT to water the almond trees. He said they were indigenous and that no one waters the wild almond trees in the campo. This is true but they are established trees and, somehow, came through their early stages without help. We do water the almonds sparsely but we are still not sure what is the best thing to do.
The other thing we have noticed is that in the height of the Summer young fruit trees simply burn up. The leaves get toasted, burn, dry up and fall off. The sun is too fierce. Trees we have planted in semi-shade do better for us.
). My 5 year old lychee has barely ever produced flowers and only one fruit that disappeared overnight 
The mature fig tree has never produced edible ripe fruit. I have looked it up and it seems to be the 'wrong sort of tree' that will never produce juicy ripe figs. Our avocado got some disease a few years ago (the locals call it araña rojo) and dropped dead.