Trials with Freeze Pruf

[Dypsisdean]

Discussion thread for Trials with Freeze Pruf. If you would like to add a comment, click the Post Reply button.

[Dypsisdean]

Justin,
As you know, my ongoing experience with freeze events is a thing of my past. However, during my (too) many experiences, I was intrigued by a variable I don't often hear discussed. And one I was reminded of when you mentioned your "in ground" palms.

It always made sense to me that the root structure of the palms was very important. During one freeze I noticed that some palms I had just planted fared worse than the same palm, same size, same location, that had been in the ground a year or two.

So it only makes sense to me that plants with more roots may experience a different effect due to the extra mass and/or internal liquids. But that also made me think that, of course, the roots of a palm in the ground, would be much harder to freeze, and be more spread out, than the roots of a palm in a small pot above ground. In addition, bigger pots - harder to cool, dry soil - easier to cool, heavy soil - harder to cool, etc.

But at the very least, IMO, plants in pots react very differently than established plants in the ground. And, IMO, this may not be related to the overall "health" and vitality of the plant, but the physical phemonomon of being "above" ground, with the roots surrounded by the very cold air. I think a palm can be just as healthy and vigorous in a pot. But I don't think it can fare as well during a freeze as one in the ground, all things being equal.

[palmnerd]

Dean,
It would be interesting to hear more reports from growers who work a lot with the container culture and hear what, if any protective measures can be taken with hundreds of potted palms in an event such as this recent cold spell.
I use Ptychosperma elegans a lot as my torture subjects. I had a batch of spike seedlings a couple of years ago, exposed to pretty cold weather, they were only in 4" pots at the time. They likely took <32f three or four times that winter. They were unscathed. When I was stepping these plants up the following summer I noticed a lot of earthworms in the soil in the 4" pots. I couldn't help but wonder if the strong concentration of wormcastings and worm "tea" didn't act in some way to aid the vulnerable seedlings through the process.
It seems palms have very tempermental roots. So I agree with your observations and that everything you can do to help insulate them from harm is another means of insuring success. Right before this last cold spell, I went out to my favorite horse farm and loaded up on horse manure and stable castings to ring around all of my in ground palms. The bioactivity in the decomposing horse offerings seems to help a little in warming the immediate area of the palm where the roots are. It also feeds the plant a bit as well. I also use pine needles quite a bit to further insulate the ground around the palms.
Also regarding palms with more root mass. I wonder if the success of some of the dry tropic palms in marginal areas like central Florida and other areas is due to the rather deep roots they throw. Coryphas Hyphaenes Borassus and others seem to adapt well in most regards.
Rainforest palms don't need to send roots down as deep and it's hard to keep them alive here. Is part of the reason the shallow roots? I'm sure most them die at the heart long before roots play into the cause of death but would a better or deeper root system help some of these palms. Is there research fodder in this area?
It seems to me like it's just a matter of time when the cost of genetic manipulation comes down enough to see the tropical plant industry developing freeze resistant palms etc.. they can add genes from subartic evergreens to the palms and get an expression for antifreeze in the internal tissues. They're doing this stuff with cash crops like cotton these days. So why not?

[Dypsisdean]

Is there any genetic manipulation that has yielded a more frost tolerant plant to date? I don't think I have heard of anything yet in that regard. Maybe adaptable to cooler or warmer climates, but not a success at producing something that would withstand a freeze that wouldn't have done so beforehand. I doubt if it's as easy as one or two genes. And I doubt it would be worth, what would be a considerable expense, to make a plant able to withstand 30º instead of 32º. It would have to be a much larger benefit to be worthwhile IMO.

[palmnerd]

I agree, which is why I prefaced the point that the cost of gene splicing will have to come way down. Do I think there is a demand for landscape plants in marginal areas? I think a lot of resort towns would pay for that edge in having the appearance of being subtropical. Casino\resorts scrutinize their layout to the highest degree to squeeze out every consumer dime they can.
If they can get cotton plants to excrete a natural pesticide from another unrelated gene set, then it makes sense that you could fuse a gene to a palm species to express a chemical that would help it withstand cold. I certainly know nothing of gene work but I can intuit that some day in the future the people who make a living splicing genes will want to diversify their practice to include the landscape industry, when the price is right.

[Moose]

Freeze Pruf = snake oil