We've been back in England for almost a week now, so too late for the spring visit but just in time for planning the autumn excursion! Thankyou
Bit of an update for all those interested.
We went a bit mad with fruit trees, the voucher I got from the website that was advertising the land gave us enough for 4 varieties of apple, a plum, a pear and 2 cherry trees (please don't ask what variety, it's in our gardening folder 1500 miles away!) my girlfriends mum came along with us and bought us a persimmon, another plum, an orange and a pink grapefruit (again, please don't ask, the labels were in Portuguese and are also 1500 miles away!) not to mention the blueberries, raspberries and gooseberries we took over with us!
Planted everything up on the top terrace, cleared the grass from the planting areas and built up guilds where we could with what we had. We were given some walking stick cabbages by (the girlfriend) kris' grandad, and we have plenty of mint and lavender growing on the land already so we spread these out amongst the trees. After everything was planted we sowed a spring ground cover mix (need to check the website to remind myself what was in it!) some red clover and a mixed bag of legumes, and covered with a good 30cm of grass cuttings, leaf mold and dried leaves to try and keep some of the moisture in. In total there is now 6 lengths of hose fitted into the pond wall just below the outlet for the overflow pipe I put in. The hoses run in pairs to water 3/4 trees each so they basically run from the pond, round the trees and then back to the pond. I figured this way it would minimise the pressure drop created by each section of Soaker hose.
Although water does seep out, I don't have much hope for the trees at the front of the terrace! However, even after putting in the overflow pipe the back edge of the terrace still has plenty of water in the ground so it wasn't all just spilling over the top like I'd hoped! This does help the trees at the back though and I think they'll have a much better chance of survival. We dug a hole to get some clay to seal up around the overflow pipe and the next morning there was 30cm of water sitting in the bottom, hopefully this'll keep them alive but time will tell!