River's Edge
Masterpiece
I cannot speak for the Eastern Hemlock, but i would judge wether the location is right by the color of the foliage and vigor of the tree. Hemlock in the right location growing vigorously is a dark luxuriant green. Too much sun and they turn lighter with yellower foliage. They do not like to dry out .You just use partial shade after collection, correct? I had my eastern in partial shade for the first year (collected late spring) until it started to show signs of growth following year. Then I move it to as much full sun that I had in my yard.
Actually the mountain Hemlock is primarily an understory type tree, towered over by Fir and Douglas Pine. They healthiest specimens thrive in the shadows, so i keep them in Partial Sun/Shade all the time. There color and health is always better when not in direct sunlight or direct drying winds. The best location i have for them is an area that gets full morning sun, shaded in the hottest part of the afternoon and receives the light late afternoon and evening.
This is in keeping with cooler temperatures at higher elevations where they grow naturally.