Bismarkia in colder climates

[NorCalWill]

For those of you growing Bismarkia in a climate that is prone to regular winter frosts, with some heavy frosts, have they shown less damage the larger they are? I planted a fairly small one last summer, had 5 small leaves, and it is doing better than I expected after a pretty frosty winter here in Northern California. Only about 30 percent of each leaf has turned brown, compared with 90 percent turning brown on one that I had in a pot about 5 years ago. As the roots grow deeper, and the plant gets bigger, will frost damage decrease?

[Trópico]

I have two mid to large ones, no trunk yet. For me, it depends on the severity of your overnight lows. Absolutely no damage last winter (prolonged cold with subfreezing temps, the minimum not as low as this winter) but significant damage to outer leaves this winter (no prolonged cold but lowest low 23.5°F). But in general you should see more damage on smaller specimens than large ones.

Edited January 27, 2011 by Trópico

[sonoranfans]

We have had 2 significant consecutive frost events here in december, but only bottomed out at 28.5F. I have a 6 footer and a 30"(7 gallon size), both with no overhead or nearby structure. The damage to the smallest was ~50% and a little less for the 6 footer. The smallest one popped a new greenish spear, looks good and has a few purplish fronds and the lowest fronds are burnt. the 6 footer has frost damage that is spread out more over the fronds, but less concentrated burning. Larger bizzies in the area(>15') look undamaged to my eye. Some of these are in areas where larger royals(>25') show plenty of burn on lower fronds. It might be that overall height and getting the roots established is important and it may also be that wax production is important. Wax production can be genetic, but also it increases with increased sun exposure. Wax will insulate leaflets better with a thicker layer.

[_Keith]

I am in Zone 9a and have killed too many of them already. I'll leave them to the Zone 9b or higher, and frost free folks from here.

[Alicehunter2000]

I have 5 in the ground. This is the third winter for some of them. I have noticed more damage from frost than from prolonged freezing temps 12 plus hours of freeze for many nights over the last two years. They seem to me to have approx. the same hardiness as queens. Some do better than others. I have put supplemental heat via Christmas lights on most of them but some had no heat on a few of the freeze events and did not seem affected. I have one that is sheltered by an Oak tree that has not had even 1 frond burned due to cold....this is also the same one that did not get supplemental heat several times.

These guys are definately hardy to prolonged sub-freezing temps above 25 F.

One thing I strongly advise is to put them in the ground as any freezing weather while still in the pot may result in a quick death....they don't like cold roots. I lost a beatiful healthy 35 gallon that way.

[Tala]

yet to observe any increase in cold tolerance as they age, here anyway - either they are cold hardy (for my purposes, down to 23f so far) as 3 leaf sdlgs or they exhibit damage at that age, and never perform any better. I've experimented w/ them over the yrs, leaving out many in buckets right out in the open. Now that my mature plants are reproducing I don't worry about trialing anymore, these never show any damage. As mentioned above there is some definite variability w/ them, from cold hardiness thru color, growth rates.

[floridagrower]

There is a hotel here that has a row of them that have been there several years. The lack of damage is surprising. Even after these past few winters they look decent.

[Walt]

From my observations and experience, I will give a slight edge to larger bismarkia palms having more frost/cold hardiness than smaller ones, at least concerning radiational freezes. Where I live, 99 percent of my freezes of any consequence are raditional in nature (no wind and clear sky).

Last month all of my bismarkia palms were cold/frost damage to some extent. I have a small one (not shown below) that I planted last summer and it was completely fried. The first photo below shows my next to smallest bismarkia. It was, for all intents and purposes, fried.

The bottom photo shows my largest bismarkia. Only the bottom fronds were fried. The top fronds were either not damaged or only got slight tip burn. However, this might be attributed to the air being slighly warmer higher up, since air is always stratified during radiational freezes. Still, all other things being equal, I would guess a mature bismarkia palm would be slightly more cold/frost hardy than a very small one. Of course, that probably holds true for most palm species.

The below palms were exposed to 20.9 degrees, plus six more nights in the low to mid 20s. The 20.9 degree reading was taken in the open and four feet above the ground.

ABOVE: Totally fried small bismarkia palm in front of green Sabal etonia palm. Note totally fried Philodenron selloums in back ground on right.

ABOVE: My largest bismarkia palm showing burned leaves on bottom half and mostly undamage leaves on top half.