Yellowing fishtail - Epsom salts?

[Christopher Dillman]

I've had this fishtail for almost 10 years now. Took at hit with the recent cold spell here in San Diego, CA. What was once bright green leaves have shifted to the yellow hue.

Considered leaving it be, and just be vigilant with the Palm Plus feeding before any big rains come. 

Or..

Worth giving it a hit of Epsom salts diluted with plenty of water?

 

 

 

[Darold Petty]

I have a Howea with the same symptom,  I hope someone has pertinent advice !

[Tomas]

On 3/8/2023 at 8:31 PM, Darold Petty said:

I have a Howea with the same symptom,  I hope someone has pertinent advice !

Looks like a serious nitrogen deficiency to me, but magnesium may also be lacking. It is important to bear in mind that the administration of magnesium also requires a supply of potassium, and therefore the best fertilizer is SulPoMag

[Darold Petty]

Tomas, thank you !

[Johnny Palmseed]

It’s probably not a Magnesium deficiency since the whole thing looks yellow. Normally, Mg deficiency shows as yellowing along the outer portion of the oldest leaves while retaining some green along the inner. And usually the newest leaves will be green. I’m not sure if Caryota are as susceptible to Mg deficiency like Phoenix palms are but it looks more like a Nitrogen deficiency since the entire palm is a pale yellow. I would not try to target a deficiency but instead use the Palm Plus as it will be less likely to throw things out of balance. It could also just be showing signs of stress due to the cold temps which obviously would require time to grow out of it.

[Patrick]

Yeah, I was going to say that yellow all over = Nitrogen.  If you need nitrogen, Ironite may be a good solution. There are other good options if you want to go organic. Try Blood Meal, it's 12-0-0. At work here we have bags of ferrous oxide (rust) that I've heard can work well, but that's just my work, and then sounds similar to that thing called "Ironite" mentioned earlier.

 

It's just starting to warm up again so uptake should be getting effective again. It should be time for me to fertilize in a week or two. I bet you could do it now down there at the bottom of the state...

[Tracy]

2 hours ago, Patrick said:

It's just starting to warm up again so uptake should be getting effective again. It should be time for me to fertilize in a week or two. I bet you could do it now down there at the bottom of the state...

In a normal year I would say yes, one could start fertilizing about now.  This has hardly been a normal weather year down here or up in your part of the state.  I'm waiting another week to see what happens on the back end of the storm due to arrive overnight down here Tuesday into Wednesday before thinking about fertilizing.  Caryota's seem prone to yellowing here needing plenty of iron and a good slow release fertilizer.  I've seen yellowing like this at the end of winter in both heavy clay soil at my house in Carlsbad (Caryota obtusa/gigas) as well as in Leucadia's sandy soil (Caryota urens or ochlandra).  Len pointed me in the direction of chelated iron when you can find it.  I don't remember which product I currently have still in inventory, but I switched over to buying chelated iron for better uptake several years ago on his advice.

Good luck Christopher!

[Johnny Palmseed]

I used to use Ironite quite a bit as a good lawn supplement. But Pennington bought it and the price went through the roof. When you look at what you’re getting (1-0-0), I don’t think the price is justified. It sells for $2/pound locally. There are so many fertilizer formulations available, I would think that you could find a good palm fertilizer with extra iron/sulfur in it for no extra cost.

[sonoranfans]

I agree with tracy on Fe, though there are probably multiple deficiencies at work.  Yellow on newer leaves is most consistent with Fe deficiency, nitrogen, Mg would be biased more to the older leaves.  Use chelated iron and sulpomag along with your palm fertilizer when it warms up.  If its cold out there is no point in putting fertilizer down.  I would not put Mg down without the proper K ratios that is why they have sul(S) po(K)_ mag(Mg) as the ratios of Mg, K are important.  You might get away with it in clay soil where K can persist but in florida I would never add Mg without K.  I have had good success with sulpomag which is also marketed as K Mag and langbeinite which is the naturally occurring crystal.

[Merlyn]

I had a smaller Gigas/Obtusa do that after then January 2022.  It defoliated at about 27F with frost, and the new fronds grew out lime green and never greened up.  I tried Osmocote, Lesco 8-2-12 palm fertilizer, a bit of SulPoMag late in the summer, nothing helped the existing frond green up and the new ones kept growing in lime green.  FINALLY I tried Southern Ag Palm Nutritional Spray on it around November.  I sprayed all the leaves and it started looking better in a week or two.  It got torched again with the Christmas and mid-January freeze.  The new frond came out looking a bit more green than last year, so hopefully the spray worked.  It is 2.5% Manganese, 1.5% Magnesium, and 1.0% Iron.  I suspect it is the iron that it needed.

[sonoranfans]

13 hours ago, Merlyn said:

I had a smaller Gigas/Obtusa do that after then January 2022.  It defoliated at about 27F with frost, and the new fronds grew out lime green and never greened up.  I tried Osmocote, Lesco 8-2-12 palm fertilizer, a bit of SulPoMag late in the summer, nothing helped the existing frond green up and the new ones kept growing in lime green.  FINALLY I tried Southern Ag Palm Nutritional Spray on it around November.  I sprayed all the leaves and it started looking better in a week or two.  It got torched again with the Christmas and mid-January freeze.  The new frond came out looking a bit more green than last year, so hopefully the spray worked.  It is 2.5% Manganese, 1.5% Magnesium, and 1.0% Iron.  I suspect it is the iron that it needed.

Iron is most often associated with overwatering or alkaline pH from what I have read   Foliar spray works in those cases as the alkalinity does not come into contact with Fe as Fe+ OH=> FeOH (insoluble in water and not bio available).  I have used foliar with some success but to keep the yellow away consistently it is easier with a chelated Fe.  And no I dont use ironite, its a mediiocre source of iron.  According to UF Gainesville ag dept, florikan was superior in consistent delivery of nutrient delivery through time.  The osmocote nutrient delivery petered out early vs its day rating.  If a palm does get deficient though, a controlled time release fertilizer alone may not correct it.  Thus sulpomag and chelated Fe will work better to correct a serious problem.  

[Looking Glass]

This guy looks pretty beat up.  If it were a strictly nutritional issue, I’d assume it would take a couple of years of serious neglect for it to get that bad.  

It seems like it could just be cold/chill damage, in which case, fertilizing might not be a major deciding factor, but could help a bit.   

If your soil is alkaline, ferrous sulfate/Ironite will have about a 0% bioavailability to the plant.  EDDHA chelated iron would normally be the way to go, and have decent availability.  
If your soil is soggy, foliar spray can bridge you to better conditions.   As a test you can spray foliar iron, if you get green streaks and spots, you know iron is a problem.   Iron sulfate with a little soap, or Iron glucoheptonate work as sprays, but some palms seem to spot up a bit with leaf blight from this sometimes… seems to depend on the species.   

Probably helpful to hit it with a top quality palm fertilizer and sulpomag/langbeinite either way.   Maybe it just needs some warm weather and sun though.  

[Tracy]

19 hours ago, Merlyn said:

I sprayed all the leaves and it started looking better in a week or two

The fastest working spray I have found for winter yellowing is an acrylic spray paint.  Candy apple green is my favorite with metallic flakes.  For the bigger Caryota's you need either a really big ladder or a good boom lift to get it all and minimize the overspray.

[Merlyn]

1 minute ago, Tracy said:

The fastest working spray I have found for winter yellowing is an acrylic spray paint.  Candy apple green is my favorite with metallic flakes.  For the bigger Caryota's you need either a really big ladder or a good boom lift to get it all and minimize the overspray.

I haven't tried that yet, it would be easy on mine because it's only about 4 feet tall.  I have seen people paint their gravel yards green...   

I read a research paper a while back where they grew palms in sterile media and introduced nutrient deficiencies by depriving them of nutrients in the water.  I wrote down that Caryota and Arenga both got random splotchy dead spots in the leaves due to potassium deficiencies.  They noted it looked different than potassium deficiencies in Phoenix and other species.

I checked out my defoliated Gigas/Obtusa again today and it's got a spear that is now opening.  It is a lighter shade of green, but looks a LOT better than last spring's "recovery" frond.  I have sulpomag on hand and will try that, but I don't have any chelated iron as @sonoranfanssuggested.  My soil is somewhat acidic, so I could *maybe* get away with some of the other chelates.  But EDDHA is probably the best option anyway.  Any favorite brands?  I see Fertilome and GrowMore as readily available options.  I'm thinking a powder type would be the easiest to store for a long time...