Loss of colour

Is it in the shade?

Hi
I suppose it gets half a day of full sun (when its out!).

This happens to some varieties as they age , New foliage comes out reddish and ages to green, but before long Autumn colour will set in. This year has been one of the dullest and plenty of rain has made for richer growth. The colour darkens when the trees are under stress as is usual in a dry summer.. Blame it on the weather.

Mine gradually goes greener through the summer. I think it's normal for some maples. Depends on the variety.