There are far more experienced people on here than me, all I can say is I sympathize. I tried 2 different hinoki false cypress in a part shade, pretty protected spot and they had the same unhealthy browning after a couple winters and then finally died. You can wait to see how it greens up this summer but otherwise I don’t think there’s much you can do.

If not weather, for it to do that after 3 years I'd suspect a root issue. Are you sure it was just a normal winter? We had near record cold down here.

tj

Thanks guys. That green thing was the rubber coated plant wire for the support stick in the middle. Arrgg... ok... let me check check the root. I have pretty good layers of mulch before winter for protection. So, what was the cause? Was it not enough water during winter? Sun burn?? or was that some kind of plant disease? perhaps this type of plants are not hardiness enough for Canadian winters at all? My other shrubs and trees are totally fine and healthy, just this Thoweil Hinoki Cypress made me sad.... :( I will try to trim off the brown and see what happens, I guess nothing else I can do...

Hinoki cypress are known for accumulating dead foliage on the interior.......and that is completely normal. But this is well beyond just the interior die-off!

Was it exposed to a lot of wind during winter? And I'm not sure that is even relevant as both wind damage or sunburn would not create such a random pattern of brown or dying foliage but would be more focused in their location.

With nothing else to go on, I'd suspect some root issue. Perhaps congestion that was not adequatey addressed at planting and is now rearing its ugly head.

I was going to say wind exposure too but I agree the dead parts appear pretty random and spread throughout the plant. At the same time, the siting does look pretty exposed and susceptible to wind, is that correct? As I said, I gave up after 2 dead hinoki due to Michigan zone 5b winters. I think they either aren't completely hardy for our conditions or need that perfect protected spot. And like you, I do have a nana gracilis and some other false cypress in more protected sites that are doing great, there was just something about the hinoki and/or where I put it that didn't work out. I hope yours hangs on and puts out some new growth this spring/summer, if it does snap back maybe move it to a more protected site or wrap it during winter.

Any updates on this tree?