The leaves on our two year old walnut tree have gone a bit yellow. What should I give our tree to stop the yellowing? Thanks. Jane.

Walnuts are deciduous and lose their leaves over autumn and winter, the leaves turn yellow and drop off. Is it the new growth that is going yellow or is it the old leaves? If it is the old leaves then this is normal. You can feed walnuts with a nitrogen rich fertiliser such as Tui NovaTec Premium fertiliser in early spring, also mulching around the tree will be beneficial to ensure the soil is kept moist through the summer months, a quality mulch such as Tui Mulch & Feed is a good source of nitrogen as well. Using Seasol around your walnut tree is also beneficial - it is a seaweed based plant tonic that stimulates root growth and overall plant health.