Hmmmm,
yes, i was aware of the "armoured or not" options, and i found this cable on, -sorry- ebay, which states:
NYY-J PVC HI-TUF BLACK 2.5mm 3 CORE OUTDOOR CABLE
so i thought in a conduit it would be fine, and yes, partly buried, but in conduit all the way. And i must say, i think i gathered...