Thank you so much, for the advice!!! I am just back from Orihuela Costa and planted Teucrium, Tecomaria capensis, Schinus molle, Aloe arborescens, Pistacea lentiscus. The other plants you adviced were not to be found, the garden centers here are not very good, the plant selection narrow and the plants very dry. In addition to those mentioned I planted Rhapiolepsis, Callistemon, Metrosideros, Ceanothus, Coronilla, Polygala and Grevillea adding a lot of compost and composted manure. I have some lantana camaras in the garden from the previous owner, but they look quite awful, very dry, leaves light green and brown. I pruned them back hardly (to 50 cm), I don't know if it was the right thing to do, must wait now what happens! The bougainvilleas look also completely dried out, I left them as they are, what would be the best procedure?
Yes, I know that the overhead irrigation is no good, but before the I have the trees, shrubs and the flower beds in place, I am not able to change the system. I am having someone to come in and water deeply once a week in addition to the irrigation. I haven't seen roses here, but I have roses in Basel, Switzerland, where they thrive ideally! Good gardening for you!