Boston Ivy - not thriving anymore
 

Hi,
I have Boston Ivy growing all over the south facing wall of my house.
Location - Cleveland - North Yorkshire. I suspect it was planted over
35 years ago. For the past 30 years it has grown like wildfire. The
main trunks are as big as your leg. However a couple of years ago I
noticed that the bottom foot or so was not doing so well and was
actually bare in places. I seem to remember the leaves used to be that
vigorous that they would spill over the pavement next to the house.
This year despite recent warm weather it is still not in full leaf. In
fact some of the buds appear to have "stalled" and are not developing.
I have 3 concerns. 1 it is dying of old age. 2 it needs feeding. 3 it
could have been sprayed with a herbicide "inadvertently" by the
council.
Ten years or so ago when we had a drought during the summer it still
remained in full green leaf until the autumn. Nearby grass dried out
completely during this time.
It has only ever been fed once when we relaid some paving slabs and
scattered an amount of bonemeal under them.
So, any ideas anyone?
Should I feed it? If so what with.
Should I try to propagate it this autumn - or earlier?
Do the symptoms tally with herbicide exposure 3 years ago?
Needless to say the council do not want to know anything about it.
RK