PlantFiles: Canadian Hemlock, Eastern Hemlock
Tsuga canadensis

Beautiful tree in youth. Tends to get ragged in adulthood in central NJ, though this may be more due to the dreaded Wooly Adelgid than the climate or pollution. Would be positive if not for that dreaded insect, but its decimated too many forests (almost all of NJ's native hemlocks have been wiped out) to vote positive.

Not native to this region; it is grown as an ornamental. The light green young needles make a pleasant tea rich in vitamin C.

Trees are pyramidal in shape with finely textured needles. Soil needs to be somewhat rich in organic material and well-drained or the tree won't do very well. It can be propagated by seed or by stem cuttings. If planting this tree for the first time, water it regularly for the first year (careful not to overwater it, or root rot may set in).

Canadian Hemlock is native to eastern North America and in the wild can grow up to 120 feet with a tall single bole, but in cultivation usually only reaches 80 feet. Most of the young growth is shade tolerant as it becomes part of the understory within a forest.

Leaves are toothed and mid-green above, silver underneath. Female cones become pendant and drop off during the second year. It likes humus-rich, moist but well drained, slightly acid to marginally alkaline soil in shade to full sun. It also does best in shelter from cold winds. Propagate by sowing seed in containers in an area protected from winter frosts or by rooting half-hardened cuttings in late summer to autumn.

Canadian Hemlock is not poisonous and Native Americans in eastern Canada made a refreshing medicinal tea made from its bark and twigs - it has no connection with the plant of the same name.

This is not a negative comment on the plant itself- which I really like, but it is being decimated in the Northeast, and maybe other regions unknown to me, by the Wooly Adelgid.
I have a number of these fast growing, evergreen trees, and one of the largest is dying for sure. I treated it with a systemic insecticide- which I don't like using, but the Adelgids are back and the cost of the treatments it will need to save it are too high. A natural predator has been found and this is still in the experimental stage, as far as I know. I hope it becomes available before it is too late for the trees.

I planted two Canadian Hemlocks on my property last year and they are doing fine in only a few hours of sun a day. They are known to be the lowest light evergreen tree. The Hemlocks around here get kinda leggy and seem to grow to only about 40 feet tall but about 30 miles away at Longwood Gardens outside of Philadelphia, they have the biggest specimens that may exist in NE US. Giant 120 to 140 foot trees. I can't imagine they get any bigger anywhere.