Clematis going yellow

I have a evergreen clematis, that flowers in the winter, but it is rapidly going yellow, I have looked at the tips and they are still green. Can I rescue it ? What is wrong?

We've had such a lot of rain this year that maybe nutrients have been leached from the soil and it is suffering mineral deficiencies.  Clematis like alkaline soils but still need iron and magnesium to function well so try giving it a liquid feed of iron rich food for ericaceous plants as an instant tonic.

You could also give it some calcified seaweed as a general tonic and a foliar spray of Epsom Salts - 2 tablespoons per gallon of water - which will give it magnesium.

I have the same problem with nellie moser she is rather jaundice but she is doing her second flowering.I wondered if I gave to strong a feed to soon or is it too much water but she normally likes alot to drink.anyway will try your advice.I did give it a nettle feed .

obelixx thank you for your advice, I thought that I had lost it , I will go out this weekend and get some feed for it.