Tree, what tree?

This is the stretch of coast along which Tom (Liam Neeson) and Joan (Lesley Manville) walk in the film Ordinary Love.  They always go to the same tree and turn around again.  Except there is no tree.  Did they put it in by some fiendish bit of post production?  The tree tells the seasons as the film progresses (bare, in bloom, in full leaf, bare again).  I doubt if they filmed the full year round, so maybe there is some credence to the hunch that they put it in afterwards.