They do like to be in a full sun situation and have a slightly acidic soil, I think given time as it matures and grows then the autumn colour will be as it should be.

Thanks Julien. That’s what I was hoping that with time it will show its true colours.

From what I've seen, the leaves turn yellow first, then turn orange and red as autumn progresses. Julien is also right: younger trees tend to be more yellow than orange.

Thank you Tugbrethil, guess I will have to be patient and wait a few more years!

also colours develop better after a hard frost. The Yorkshire arboretum have several and they have been disappointing this year and they think lack of frost is to blame.

That’s good to know thanks Seaburngirl.