I have never had problem to leave my phal for 2 weeks (except in August, I tend to ask my neighbour to water them). I am based in uk too. My worry usually is for the finer roots like oncidium (maybe I stress too much) or odontoglossum. I tend to group all the orchids together, I place them over tray full of stones and water to keep the moisture up and I pray the Orchid goddess
