We planted 4 new 2 year old Clematis montana rebens plants late this spring. Three are against a north facing fence and all are doing well. The fourth one is planted on a west facing wall on our garage and is not doing well. I've posted pictures of a leaf of the one on the garage and another picture of the same plant on the fence. The one on the garage is still growing well with good runners but the leaves look weak and discolored even when they are young. All have been watered carefully and no insecticides were used even when the leaf cutter bees were actively making holes in the leaves. The soil is the same in both locations.

Any ideas and suggestions.