Fall Fertilizer - add potassium ?

[FRITO]

looking at http://www.cooltropix.com/

found some interesting info here: http://tct.netfirms.com/tropics/coldfert.html

"To increase the cold hardiness of palm trees, coming into winter, use a granular potassium fertilizer like 0-0-60 or something of that combination that is applied 45 days in advance. It needs to be applied at least 45 days in advance in order to get into the plant's system. What the potassium does is strengthen the cell walls of the plant and will displace the amount of water in the cells making it harder for them to burst during freezing temperatures. Water freezing, expanding and bursting. "

should I go find some potassium? may help marginal palms I am growing such as P. roebelleni and R. rivaulris

anyone deliberately add potasium before winter?

[SubTropicRay]

Hi Luke,

Despite what the experts say, I fertilize in late fall to make the palms more hardy. My experience has been that the salts in the fertilizer make the plant more cold resistant. I use an 17-3-8 mixture.

I'm still reeling over the goal line fumble last week.

Ray

[waykoolplantz]

Atlantic FEC screwed up my delivery this week...so we went & got a ton of Lesco 8-2-10

[sonoranfans]

looking at http://www.cooltropix.com/

found some interesting info here: http://tct.netfirms.com/tropics/coldfert.html

"To increase the cold hardiness of palm trees, coming into winter, use a granular potassium fertilizer like 0-0-60 or something of that combination that is applied 45 days in advance. It needs to be applied at least 45 days in advance in order to get into the plant's system. What the potassium does is strengthen the cell walls of the plant and will displace the amount of water in the cells making it harder for them to burst during freezing temperatures. Water freezing, expanding and bursting. "

should I go find some potassium? may help marginal palms I am growing such as P. roebelleni and R. rivaulris

anyone deliberately add potasium before winter?

Yep, I fertilize a few weeks before an expected cold snap. THe theories presented above are logical(freezing point depression) and physically based, but the 45 days till absorbtion, I doubt. I can see my palms respond to iron much quicker than that (in 60-65 degree avg weather), and iron moves slower throught the soil(mobility), and plant membranes than potassium. I think three weeks with a deep water would be fine.

Edited November 8, 2008 by sonoranfans

[Tala]

I wish iron would do that here, it leaches out faster than almost any mineral we use.

As to the subject matter this is a resounding yes. I've authored several articles as testament to this, might be one on me old website, and will admit Dr. Donselman was the inspiration for this. The overall effect isn't noticeable beyond a few degrees/hrs below freezing but very often that is all one needs to get thru a winter here. I would imagine the colder your "mean" winter conditions are the less effective this technique is, but for a climate where palms never really go completely dormant it does work. I've added extra N to this with no ill effects as well, the idea is to get the salt content jacked up as high as possible.

[sonoranfans]

I wish iron would do that here, it leaches out faster than almost any mineral we use.

Very interesting Tala, as a chemist I would suspect that higher pH soils hold iron better than acid pH soils, especially in the presence of nitrates. My soil is alkaline, and I never suspected it was an advantage, though it seems I learn something almost every day. Free or soluble Iron would have less mobility(in diffusion processes) than potassium or sodium due to its much larger atomic radii. However, it would be logical that highly soluble iron would rinse out(not diffusion but convection) quite quickly (its highly soluble in an acid soil). I see the "green up" effect of iron addition in 10 days to two weeks.

[Palm Guy]

Hey Luke,

Sounds like a good idea but try it on a palm you don't mind losing FIRST.

You generally want to keep the Potassium to Magnesium ratio at about 3:1 or close enough or else you will have Magnesium deficiency symptoms(Mg deficiency isn't deadly to palms).

Salts are usually a bad thing to have in the soil (in large quantities) if the soil is kept on the dry side - not too much of a problem on wetter soils.

Might be worth a try. Let us know how it goes.