I have a beautiful very tall plant (approx 12 feet tall) in my garden but I have no idea what it is....any ideas please?
It is a Pieris. It should have beautiful young red leaves fairly soon.
Pieris, like acid soil same as Rhododendrons
Pieris 'Forest Flame'
If it seems happy then it's probably in the right place. Ideal requirements are a sheltered site in shade or part-shade in moist, peaty, acid soil.
Cut off any frost-damaged spring shoots as soon as possible. Dead-head after flowering to improve growth.
You could give it a mulch of ericaceous compost now and again in the autumn.
I agree this is Pieris sp.
However, it does not look right for Pieris Forest Flame as this usually has the red new leaves which I would expect to see.
Could it be Pieris Mountain Fire?
Pieris japonica Mountain Fire is another with red new leaves.
No sign of that in picture.
I would not like to guess which Pieris it is from one small picture.