tomatoes and woodash

Maybe just a dilute general liquid feed to boost nitrogen levels?

Looking at what the RHS have to say about woodash, they don't seem to think its a "good idea" to put woodash on the soil at this time of year.

As you have, I would not put any additional fertiliser unless the plants look a bit weak. I would watch out for magnesium deficiency because that seems to be caused mainly by high potassium levels which the plants take up in preference to magnesium.