Just an odd thought I had about Palm Heartiness.  We're all zone-pushers, whether in ground or in container ranch.  So when the weather gets cold do you worry more about the lowest temp, or the duration?  

I see the Floridians trying to cover small palms, etc. when the arctic express heads too far south, but those events are usually one overnight low and maybe some lingering coolness.  What happens when the temps are slightly above your danger point but stay there for a long time?  Maybe no freeze damage, but is there a metabolic effect on the plants? 

Example, we've had a really early cold weather event on the Great Plains.  I have stuff still outside (because it's still technically summer) that I don't usually worry about until the overnight lows dip below 40F.  However, this cloudy rainy crap is on its 3rd day, and more tomorrow.  While the temp has never dipped below 40F, it's been hovering in that 40-45F range the whole time with no sun.  

Am I right to be worried?  Or does just the lowest number matter?

2 minutes ago, Funkthulhu said:

Just an odd thought I had about Palm Heartiness.  We're all zone-pushers, whether in ground or in container ranch.  So when the weather gets cold do you worry more about the lowest temp, or the duration?  

I see the Floridians trying to cover small palms, etc. when the arctic express heads too far south, but those events are usually one overnight low and maybe some lingering coolness.  What happens when the temps are slightly above your danger point but stay there for a long time?  Maybe no freeze damage, but is there a metabolic effect on the plants? 

Example, we've had a really early cold weather event on the Great Plains.  I have stuff still outside (because it's still technically summer) that I don't usually worry about until the overnight lows dip below 40F.  However, this cloudy rainy crap is on its 3rd day, and more tomorrow.  While the temp has never dipped below 40F, it's been hovering in that 40-45F range the whole time with no sun.  

Am I right to be worried?  Or does just the lowest number matter?

IMO, duration would often be worse than a quick hit.. Especially if, like you mention, the weather stays wet and cold over X number of days..  A dip to say 30, or even 28F, followed by a quick warm up the next day/ days following might cause a certain degree of cosmetic damage but usually won't be enough to kill things -at least not anything i grow/ have grown.. Plants might drop leaves, ..suffer tip damage to stems/branchlets but will push growth as soon as it warms again. This kind of damage would be typical here during a quick cold spell most winters..

That said, throw in several days of cool/ cold -and wet- after a freeze, and the risk of loosing more goes up quite a bit. Have lost even relatively hardy cacti to that kind of weather.  A night of frost might be enough of a shock that causes growth to slow, but most stuff will continue growing.. Extended cold/cool weather will cause stuff to really slow down or stop growing entirely.. Throw lots of water on stuff that is barely growing or completely stalled/ dormant, and all that added moisture may do is induce rot issues in the root zone. Plants will only take up so much moisture.. If there isn't much growth happening, they won't use most of whatever moisture is available in the soil..

Obviously, some plants will croak at even the slightest exposure to frost/ cold temps.. I try my best to avoid those, lol

Hi so ive started noting the lows and palm damage in my area i am in south africa just starting with spring . This past winter we had was very very harsh on my palms and in our area we have got lows of -7c (23f) and palms got burnt to a crisp sabals,washingtonia,queens,bismarckia,livistona and cidp undamaged the more hardy palms tracy and butia. They all are now pushing new growth so survived but damaged quite severly the winter came quik and wet in end may of lows of 4c to start june of -2c and highs of 16c and constant low temps but wet days on and of for about 2 weeks. The winter prior we got lows of -9c but highs of 21c and no damage to any palm of the above mentioned the lows was 4 - 7 am before and after that time it was above freezing and during the day hot enough for a jacket to be too warm and bone dry just my 2cents of what ive personaly noticed. 

Prolonged cold is worse than short very cold dips

Also depends on what species you are pushing. For tropical palms long periods of chilly/cold sunless weather, esp. with rain, can and likely will be lethal. Tropical palms, i.e., coconuts, Adonidias etc. do not photosynthesize at all below 50F and will die if temps stay low - even on sunny days. Weather in the 40s causes the ground to get cold and cold soil will kill the roots. Cold, dry winds damage tropical fronds. If your days stay reliably below 60F, take your tropicals indoors.

Here in Cape Coral, occasional winter nights drop below 40F (37F one night last season). But if the cold blast lasts only a few hours and the temps rebound fast come sunrise most palms larger than a seedling will usually survive, with exceptions - Cyrtostachys, Nephrosperma, Phoenicophorium, some Areca spp. But they will suffer damage. Royals suffer tip burn at temps in the low 40s and coconuts suffer even more cosmetic damage. Fortunately, they quickly recover when spring growth gets underway.

SFL's great saving grace is that winters are dry and generally warm, absent the occasional Arctic Express. I've lived here over 27 years and I can count on one finger the # of days it rained when temps fell below 50f: January 10, 2010.

 

What palm varieties are you worried about?

Most of the really finicky stuff is inside, or was never outside.  

Still outdoors is a D. lutey, P. robelenii, R. rivularis, a sago cycad, and some rando ginger, sea grapes, pineapple and whatnot.  None of which will be a great loss if they don't like the weather.

This post was mostly intended for discussion about cold weather days and less for advice about my specific plants.

Edited September 10, 20205 yr by Funkthulhu