Palm trees in Humid Continental climate (growing, palms, magnolias, spring)

[imnotcreativewithnames]

Palms are usually planted in subtropical climates, but can they grow in humid continentals? At least in warmer ones, such as Boston which seem to have their mean minimum warm enough for at least Trachycarpus to survive..
(several Dxx have even warmer mean minimum, for example - https://en.wikipedia.org/wiki/Aomori_(city)#Climate, https://en.wikipedia.org/wiki/Juneau,_Alaska#Climate)..

So, can palms (especially interested in Trachycarpus) survive in such winters?

[Marie Joseph]

Originally Posted by imnotcreativewithnames

Palms are usually planted in subtropical climates, but can they grow in humid continentals? At least in warmer ones, such as Boston which seem to have their mean minimum warm enough for at least Trachycarpus to survive..
(several Dxx have even warmer mean minimum, for example - https://en.wikipedia.org/wiki/Aomori_(city)#Climate, https://en.wikipedia.org/wiki/Juneau,_Alaska#Climate)..

So, can palms (especially interested in Trachycarpus) survive in such winters?

Interesting question. Trachycarpus fortunei is considered the hardiest species of its genus and is successfully grown in the UK, NC/SC, and places as far north as Long Island. It is recommended for USDA hardiness zones 7-11. The windmill palm can withstand short periods of temperatures down to 15 F but does best in a climate where winter minimums average around 41 F.

Boston is right on the border of 6b/7a and it's winters seem a bit cold on average for the windmill palm. Still, it might do okay in a sheltered location. They wouldn't grow in my humid continental though (zone 5a) Aomori is a maybe for the palms since the winter lows are warmer and it's an overall warmer climate.

I would get in touch with one of the garden associations in the area and ask if anyone grows them there and if they have had success. That is probably the easiest thing to do when you are dealing with a plant that is marginal to an area.

[Isleofpalms85]

Palm trees in humid continental climates? Not in my zone 6a Indianapolis, that’s for sure. Indianapolis is hard pressed to grow very many broad leaved evergreens outside of the hardiest hollies and boxwoods.Southern Magnolias aren’t even solidly hardy here(they suffer leaf burn and brown out and leaf drop many winters so they survive here but they usually don’t thrive), I have yet to see plants like Nellie Stevens Hollies and other plants hardy to zone 6 be more than a once in a blue moon sighting In Indy.

[Sun Belt-lover L.A.M.]

No, not Boston, and not Chinese Windmill Palms. Chinese Windmill is only technically hardy to 6b or 7a (depending on who you ask); they need 7b or 8a to be reliably hardy, and even then they need mild summers for it to happen. They do better somewhere like western Europe with more consistent winter temps and cooler summers. The same is true of the similarly-heat-intolerant Chilean Wine Palms, which you'd be hard-pressed to grow in a place like Memphis or Dallas.

Also, the best I can think of for a continental climate that MIGHT be able to support mostly-unprotected palms could be Needle Palms or Dwarf Palmettos in a place like Aomori City, Japan, and even then probably not simply due to the extreme snowfall in that particular city. Though there may be more like it elsewhere in East Asia that could, at least if you helped them along the first year and protected them somewhat in the colder minority of winters; besides, even Beijing is USDA 7b and Turpan 7a!

I still genuinely don't recommend it, though. For me, palms in a continental climate are a big no-no almost by definition. Even the hardiest ones would almost certainly do better in a 7a climate with very mild winters like Nashville or Oklahoma City (and Needle Palms and Dwarf Palmettos do VERY well in both even in the long run) than an 8a with solidly subfreezing averages like Aomori City. It's not just about how cold it gets; it's also about how long it stays that cold and how much it warms back up.

I doubt they'd last much if any longer in nearly any continental climates than a place like NYC, Louisville KY or even Wichita KS. Although some probably could sustain them in the short term, maybe mid term in exceptional cases, if helped along the first year and wrapped on the coldest days of an unusual winter.

[lammius]

Interesting discussion.

I'm in New Jersey (zone 7B) and have wondered if a Trachy would do well here in a sheltered location. I've got a good spot to give it a try nearish a wall that blocks north/west winds. And it's near the dryer vent. I'm not sure if the dryer vent would help or hurt a young palm in the winter. Anyone have experience or thoughts?

[Sun Belt-lover L.A.M.]

Originally Posted by lammius

Interesting discussion.

I'm in New Jersey (zone 7B) and have wondered if a Trachy would do well here in a sheltered location. I've got a good spot to give it a try nearish a wall that blocks north/west winds. And it's near the dryer vent. I'm not sure if the dryer vent would help or hurt a young palm in the winter. Anyone have experience or thoughts?

I don't recommend it. In addition to mild winters, Chinese Windmill Palms also need mild summers, which you definitely don't qualify for. You'd probably have better luck with a Needle Palm or Dwarf Palmetto, and you can prune the lower leaves of a Needle Palm as it grows if you really want it to look "normal."

Around here, we're in Zone 7a but with higher winter means, warmer winter days and warmer springs/autumns. People around here have tried Chinese Windmill Palms, and even the shade and clay soil they need aren't enough to save them for more than a few years. However, Needle Palms do very well here (as would the Dwarf Palmetto), and in a climate like ours you don't even have to protect them the first winter as long as you plant in late April/early May and give them ample water throughout their first growing season. There are even several Needle Palm specimens that have been growing in Knoxville and White County since at least the early 1960s, and at least one of those has even reached a diameter of 9.8 feet (over 10 feet is exceptional even in ideal climates). There's one at the UT Botanical Gardens in downtown Knoxville if you'd like to see one next time you're in the area.

[lammius]

Originally Posted by Sun Belt-lover L.A.M.

I don't recommend it. In addition to mild winters, Chinese Windmill Palms also need mild summers, which you definitely don't qualify for. You'd probably have better luck with a Needle Palm or Dwarf Palmetto, and you can prune the lower leaves of a Needle Palm as it grows if you really want it to look "normal."

Around here, we're in Zone 7a but with higher winter means, warmer winter days and warmer springs/autumns. People around here have tried Chinese Windmill Palms, and even the shade and clay soil they need aren't enough to save them for more than a few years. However, Needle Palms do very well here (as would the Dwarf Palmetto), and in a climate like ours you don't even have to protect them the first winter as long as you plant in late April/early May and give them ample water throughout their first growing season. There are even several Needle Palm specimens that have been growing in Knoxville and White County since at least the early 1960s, and at least one of those has even reached a diameter of 9.8 feet (over 10 feet is exceptional even in ideal climates). There's one at the UT Botanical Gardens in downtown Knoxville if you'd like to see one next time you're in the area.

Thank you for this advice. I'm giving it some thought. I'll do more research on the needle palm as well as some other alternatives for this spot that might be more "conventional" for my area.

[Sun Belt-lover L.A.M.]

Originally Posted by lammius

Thank you for this advice. I'm giving it some thought. I'll do more research on the needle palm as well as some other alternatives for this spot that might be more "conventional" for my area.

I definitely recommend the Needle Palm if you want palms in NJ. Good luck!