yellow leaves

Hi we moved our Robinia from a pot to a border the year before last. Last year it was fine but this year, although covered in leaves, the leaves are all yellow. Why is this & what can we do to turn it green again?

Re: yellow leaves

Reply from Kathy C

Hi Jane,
Is it in full sun with shelter? What were winter conditions like where you live? Has it been fed?
Kathy C