Really isn't much information. They claim zone 7. Not like if a salesman thought he could get away with claiming something (in this case zone 6) he wouldn't just to make a sale. So I bet the tree is zone 7ish hardy.

I have a Lagerstroemia indica 'Dynamite' Crepe Myrtle in my zone 6 yard. The plant is really zone 7 hardy. Darned box stores. Fella has lived 5 years so far. Gets some die back I have to prune out. It is the LAST thing to leaf out every year. Just about when you think its dead... Perhaps this being a decently cold winter it will die.

What the heck, order it and try it out. Many of these cultivars are newer so if you get one keep posting information on it.

Here is a link that might be useful: Good GW Thread close to the subject

With plants, you just never know what will work. Things sometimes survive where they shouldn't -- there was a self-declared "National Forest" in Alaska well above the tree line and above the Arctic Circle that consists of a single spruce tree living and surviving hundreds of miles north of all other known trees.

It's always fun to experiment. The recent cold snaps in Florida and just now in the southwest and Texas are just reminders, IMO, that nothing is a sure thing, so just enjoy it while it lasts. I'm sure there are a LOT of palms and other subtropicals in places like El Paso that were killed (I believe it fell to -2 in El Paso). People can now replant and see how many years before the next extreme event.

I say try it if it's within your budget. Might work. My blue Giant sequoia is about 10 feet tall now. So far, I've not had a fatal degree of cold in the decade since it's been in the ground. I know it's going to happen someday -- could be next week, could be 20 years. But, even if it does go next week, I've sure enjoyed watching it grow.

Here is a link that might be useful: Not a real national forest, but played one on TV ...

I have a regular Coast Redwood (not any special variety, or so ForestFarm said) in west central NJ, zone 7A. Its been down to 3 degrees Fahrenheit there so far this winter along with over 40 inches of snow, so we'll see how it looks come spring. Last winter it had even more snow, but only got down to 13.

I have a few Sequoia sempervirens that have seen 9 degrees F. this winter and showing no damage. Well, one does. A Buck decided to use it thrash his antlers on it. The tree will survive.
Mike

Greenthumbs, am I remembering right that you have some room to play with where this one tree will not be the focal point of your property?

I am grasping for reasons not to try it....

1 you compulsively worry about its death and will loose sleep either warming it up or worrying about the fella.

2, more likely, it lives but it never a perfect tree suffering some damage during bad years so it never looks right in a perfectly manicured lawn

3 it lives for a little bit as the only tree dead center of your yard then dies five years from now costing you time a metasequoia could have bee growing there.

If I remember though you collect a bit so I say try it out! Much like the Crepe myrtle in my yard the tree will be a neat looking fella and yours will be a conversation piece as well.

Here's a pic of my "Simpson's Silver" cultivar of the coast redwood..the lowest temp so far has been 5 deg F....There's usually some foilage burns every winter.

Johnny

{{gwi:332511}}

My 'Aptos Blue' appears to have been killed by the cold here in North Florida this winter. Straight species was damaged. Our lowest temps were 16-18 F. The problem was roller-coaster temps with very warm, followed by hard freezes.

I'm trying some zone pushing myself, Quercus Virginiana acorns. I have another oak that's zone 6 hardy but parents are from north Texas,pretty far south compared to Pa.If I were you, if the tree isn't super expensive try it. Make a microclimate for it if you want it bad enough.

There's a reason the native range of the coast redwood ends in extreme southern Oregon. I saw landmark local specimens up here burned by the cold in 1990, because it got below 10 degrees F. in much of the area.

Commercial sources in particular appear to routinely misunderstand or misapply the USDA zones, calling something that begins to fail at 10 degrees F. hardy to Zone 7, apparently because the minimum temperature range given for Zone 7 is 0 to 10 degrees F. They are fudging to begin with by using the warmest temperature for the zone, but the main problem is that the USDA is saying Zone 7 has an

average

annual

minimum temperature

of 0 to 10 degrees F. Some years there it will get below 0 degrees F. A plant has to be hardy to below the temperature range given to last in a particular zone.

"There's a reason the native range of the coast redwood ends in extreme southern Oregon. I saw landmark local specimens up here burned by the cold in 1990"

But presumably not actually killed? A hundred-year damaging, but non-killing, freeze is no different to a Coast Redwood than a hundred-year damaging, but non-killing, forest fire. The trees will live, regrow new branches, and can go on to reproduce.

I'd suspect a bigger reason for its native range ending in southernmost Oregon is its limited seed dispersal abilities; it hasn't had the time since the last ice age to move further north yet. Without that, I'd guess its potential successful range would extend up the American west coast to at least the west sides of the Olympic Peninsula and Vancouver Island, and probably also Haida Gwaii (but maybe not as far inland as e.g. Seattle).

Resin

Burned leaves were soon replaced. I remember few, if any effects on stems.

Oregon myrtle and tanoak also drop out in southern Oregon, and also go brown in our colder winters. Madrona and golden chinkapin grow natively up here, are also more hardy. The latter has a seemingly very slow dispersal system yet has managed to come into and out of western WA numerous times since the last glaciation, in response to changes in summer climate. Peat deposits in local bogs contain thick bands of its pollen, indicating it has been abundant here at rather frequent intervals.

Coast Redwood has been grown on the Olympic Peninsula for some time.

The only taller specimen known in the whole state was planted at Quinault Lake (Olympic Rain Forest) --a very wet site affording optimal growth

Here is a link that might be useful: Interlaken Park's lofty Redwood trees

If ALJ's observations and thoughts are correct (they seem reasonable), then Coast Redwood hasn't made it further north because of summer drought (presumably not compensated for by fog drip the way it is on the California coast), not cold.

Not many places here where they are planted in forest situations, but where they are, with no summer drought here, they reproduce successfully:

Tree 46m tall, among Abies grandis 45-57m tall:

Young self-sown tree (not a stump sprout!) 8-9m tall:

Resin

Coast redwood replaced by Sitka spruce, a hardier tree, in southern Oregon. Northernmost redwood stand avoids full outer coastal exposure, instead growing some distance inland, along the Chetco River. Groves of redwoods growing right behind low beach shrubs and forbs - a startling sight, like brontosaurs in a cow pasture - not present until miles down into California.

Southern Oregon is where Californian climate conditions finally disappear completely, distribution of redwoods etc. corresponds generally to this change. As usual, different species ranges terminate in different places and do not fit the climate distribution as snugly as a hand in a glove.

I'd think the time element coming into play would be the fact that such long-lived trees have to endure all the weather a region experiences over long periods of time, and not how long it takes them to migrate north. Outer coastal record lows fall below 10 degrees F. north of Coos Bay. And that's just during the comparatively short period people have been keeping such records.

I called someone who studies coast redwood for a living and asked them. Multiple factors are likely to be involved, but the main obvious reason for the current range - as was stated above - is the Central Valley drawing fog in from the ocean. At the far north end of the range the redwoods are expected to maintain themselves indefinitely, and where present are dominating the stand(s) - but there is more competition from other species. There is effectively no sexual reproduction of coast redwood there, western hemlock coming up abundantly instead. So, it appears the redwood does not spread north because of the native environment being too suitable for sexual reproduction of competing species and quite unsuitable for its own seedlings.

I get lots of them popping up in my yard, but it's a cultivated area, with summer irrigation. Now that I think about it, I may have had hemlock seedlings overtake and overgrow baby redwoods in a couple spots here.

That sounds more likely - I really didn't think it could be limited by winter cold kill.

Tsuga heterophylla regeneration is certainly very aggressive in the forest I took the above pics in too.

Resin

Except, again, that I have seen general scorching of larger redwoods here during a winter within my short human adult life in this area. How is a species going to exist as a wild tree with individuals living 2000 years at a latitude where that happens? Browned this time, killed another.

Western hemlock actually does best at the top of its altitude range, showing that it prefers it cold and snowy (up to a point). I wonder if sites/the site having no redwood seedlings but carpets of hemlocks might be too cold for the redwood seedlings.

Maybe someone can do a statistical analysis of the probability of more extreme cold events based on what is known to occur now. Whether it would reach below -20ð to -25ðC (the temperature at which [young] redwoods die outright above ground) - perhaps. Britain had some real killer winters in the early 1700s which killed off nearly all the Lebanon Cedars, a species untroubled by cold here in more recent history. But if something was a 2000 year cold event, would it be cold enough to kill the cambium beneath the thick bark of a 2000 year old redwood?

Western Hemlock here definitely prefers low altitudes; at high levels it suffers badly from exposure, becoming no more than a big multistemmed shrub with repeated windblast dieback. But of course we don't have the summer droughts that might be taking out your lower altitude regeneration.

Resin

At the far north end of the range the redwoods are expected to maintain themselves indefinitely, and where present are dominating the stand(s) - but there is more competition from other species. There is effectively no sexual reproduction of coast redwood there, western hemlock coming up abundantly instead. So, it appears the redwood does not spread north because of the native environment being too suitable for sexual reproduction of competing species and quite unsuitable for its own seedlings.

We were taught by the man who wrote the book that the limiting factors in its native range: to the north, fire and inland-south, water.

The ice age migrations have rearranged species distribution such that the native ranges have settled to places that rarely get really cold, so we are now experimenting in ornamental plantings to determine cold fitness. But we know the redwoods migrated south into MX to find temps in the range to which it is adapted, rather than, say, migrating upward like many trees did in the Marble Mt Wilderness-Siskiyou ranges to escape the ice and cold-dryness.

Resin, I'm sure I have a paper like that around, but we know the planet is warming and will continue to do so as we burn fossil fuels, so its a good bet that 500-year cold events are becoming less likely.

Dan

I think fire may have been mentioned by my friend as one of those multiple factors, although up here at least the outer coastal area does not burn like it does/did around Puget Sound. In western Washington

Fire is rare along the coast, as many areas show no evidence of fire for the past several thousand years*

Regarding the hemlock, what is more favorable about the colder mountain climate in the highest parts of its distribution is the reduced threat from decay fungi.

Throughout much of its range in western Washington, western hemlock will be susceptible to decay fungi and will likely die before reaching 300 years of age. This is true in nearly all forests below 1,000 m in elevation....

Because fungi are limited in their effectiveness at high elevations, such as the upper Pacific silver fir or mountain hemlock zones, western hemlock in these locations routinely reaches ages of 800+ years, even up to 1,200 years (Same)

*Van Pelt, R. 2007. Identifying Mature and Old Forests in Western Washington. Washington State Department of Natural Resources, Olympia

"Regarding the hemlock, what is more favorable about the colder mountain climate in the highest parts of its distribution is the reduced threat from decay fungi"

Ah well, not a factor here (yet), since the oldest ones are only 160 years!

So the ones at high altitude live longer, but do they also get larger, and produce more seed? (seeing as those are also measures of 'doing best')

Resin

Right bboy. In Southern OR the fire return interval is too long and redwood needs to be in a frequent fire regime and moderate coastal temps-fog.

As far as hemlock goes, they are certainly large in old-growth and they are climate-limited in higher elevations so necessarily smaller. Not sure about 'producing more seed' than lowland groves, nor whether that is an adequate measure of fitness, as 'more surviving seedlings' is the germane measure. Where mt hemlock occurs, they are outcompeted by more cold-tolerant species so are not dominant or co-dominant there. Not sure at higher altitudes that saplings can tolerate wet snow load like mt hemlock can either...

Dan

Western Hemlock seedlings can compete better in deep shade than most mentioned. That's another factor for survival.
Mike

I planted a "santa cruz"(?) in zone 6 a few years back. I had to try. The first winter, only the lower branches covered in snowpack survived. Top 3-4' killed right off.
Second winter we got about -12 to -15C prior to any significant snow, and even though well mulched it succumbed completely.

This is why I always laugh when I see those with Sequoiadendron and what not planted in zone 5 etc proud that theirs survived the first winter or so. Just wait till it grows!
I do know of a 10-15 year old Sequoia that has survived some solid zone 6 winters. While it often looks beaten up in spring/summer (too big for a thorough tidying) it survives alright. Sadly it is planted in front of a home that is loosing views to the tree- it will likely get the axe before long.

Different tree. We're talking about giant sequoia when we aren't talking about hemlock.

Dan

I planted 3 of these trees back in 2006 it is now 2023 and finally in 2022 it started growing a leader, it just kept growing like a bush, I think it was taken from a side branch cutting, but it took 16 YEARS to make a leader finally in 2 of them! the third one doesn't get much sunlight so don't know if it will survive, it had plenty of sun when I 1st planted it, but now other trees have grown up around it. all the people I know says it usually takes 7 years to produce a leader, but anyway I may move soon so I wont be able to check on its progress anymore, since its on a 3 acre property, hope the new owners don't cut them down