Wouldnt start in cold weather

[gen2c4s]

Just come back from Austria in our 30d M sport. Whilst in an underground car park tempreatures plummeted to round -10oC when I tried to start it wouldnt so I left it a tried again, still wouldnt start. I noticed a warning come up on nav screen saying something about heating and assumed it was similar to the old glo plugs waiting to warm up, it evenetually started but the hand book is useless at telling you what you should do when it does not start. Does anyone know the correct proceedure as I have never heard of this on modern day diesels. Its not happened since as I have not been in such cold condition since but it happened on two consecutive very cold mornings.