Archontophoenix Cunninghamiana fronds are burnt looking coming out of crown

[Palmiz]

I have had these Cunninghamian's for 1 years grown from seed my father collected way back. The new fronds are coming out burnt looking or fungus of some sort. Not only one but a few have that problem. Can someone please help pinpoint the problem?

[Palmiz]

Whoops I meant 11years🤣.  Can someone help me treat this, the other 5 I have are also having same problem. Its kind of an on going problem but seems to be getting worse. I noticed some scale on crownshaft but I don't think that is the cause. 

[awkonradi]

I propose that you add pictures of the whole palm to this thread.  I think that might help the experts here (not me) diagnose any problems.

[Merlyn]

Additional photos would help.  Sometimes palms get "frizzle top" on new leaves due to a Manganese deficiency.  Sometimes it's cold, fungus, Boron deficiency, not enough water, etc. 

Figures 2 and 3 show transient Boron deficiency on new leaves: https://edis.ifas.ufl.edu/publication/ep264

Figure 7 shows severe Manganese deficiency on an A. Alexandrae, somewhat similar to your photo: https://edis.ifas.ufl.edu/publication/EP267

[Palmiz]

3 hours ago, awkonradi said:

I propose that you add pictures of the whole palm to this thread.  I think that might help the experts here (not me) diagnose any problems.

 

3 hours ago, Merlyn said:

Additional photos would help.  Sometimes palms get "frizzle top" on new leaves due to a Manganese deficiency.  Sometimes it's cold, fungus, Boron deficiency, not enough water, etc. 

Figures 2 and 3 show transient Boron deficiency on new leaves: https://edis.ifas.ufl.edu/publication/ep264

Figure 7 shows severe Manganese deficiency on an A. Alexandrae, somewhat similar to your photo: https://edis.ifas.ufl.edu/publication/EP267

Thanks guys, I will post more pics right now. @Merlyn thanks for the helpful information. Does look like it's gonna be a Manganese issue. I'll try to hit it with that first. It won't hurt. thanks again

[Palmiz]

[Merlyn]

CA people might know Archontophoenix better than me, so I couldn't say that there's a specific cause.  There's some brown tips on the older leaves, which might be water, Potassium, Magnesium, or a combo.  The "middle" leaves look fairly good, maybe just a bit wind-tattered.  The "new" leaves coming out with problems might be water, Boron, Manganese, or a combo as well.  It's also possible that there's a bud infection causing some damage, you could try squirting a little household 3% hydrogen peroxide in there.  If it bubbles up there's a fungus in there.

Here's my notes on nutrient deficiencies, it might help figure out what's going on.  Generally a balanced mix palm fertilizer like Florikan or PalmGain is the best bet, and adding small amounts of extra minors as needed.  For example, I have some big Beccariophoenix Alfredii that got yellowed/browned leaf tips over the winter freezes, and I added 2-3 handfuls of Magnesium Sulfate under each canopy because the yellowed ends kept on getting worse this spring.  Adding too much minors can make things worse, because some nutrients are "antagonistic" towards others.  I.e. if you add a huge amount of Manganese then you might induce an Iron or Magnesium deficiency.  So moderation is key!

• Nitrogen - Older fronds turn light green uniformly, new fronds remain dark green until deficiency is really severe
• Potassium - Older fronds get translucent yellow/orange or dead spots on leaves, especially at the tips. Caryota and Arenga get random splotched dead spots in leaves. Sometimes tips are curled or frizzled. Always starts at tips of oldest leaves, moving inwards
• Magnesium -Yellow ends on oldest leaves first, transitions to solid green at the base of each leaf. Does not cause leaf tip necrosis until really severe.
• Iron - Many times caused by overly mucky soil and root rot. Starts with new spear leaves with yellow-green or even white, possibly with spots of green. EDDHA works up to pH of 9, 3-5oz per 100sqft
• Manganese - Lengthwise necrotic streaks in NEW leaves with dead and curled leaf tips. Similar to bands showing Magnesium deficiency. Mn is NOT mobile, so it can't be stolen from old leaves.
• Boron - Bent or necrotic or distorted leaf tips, distorted or bent spear, bands of dead spots on new fans, spears that won't fully open
• Water - Underwatering brown at the edges first, later followed by yellowing of the whole leaf. Overwatering can be drooping fronds turning yellowish and losing color
• Calcium – New leaves are stunted and necrotic, eventually growing only petiole stubs. Deficiency is rare. High pH from adding calcium can induce Magnesium, Manganese, Iron and Boron deficiencies.
• Dolomitic Lime or Azomite - Magnesium Carbonate – reduces acidity/raises pH – slower release and adds Magnesium, helps avoid Potassium deficiencies in Cuban Copernicias. 5Lb per palm on full-size Copernicias and a bit less on Kentiopsis Oliviformis
• Garden Lime - Calcium Carbonate – fast release but works well. 5Lb per palm on full-size Copernicias and a bit less on Kentiopsis Oliviformis
• Sulfur - Elemental sulfur powder or prills reduces pH, 1/2 ounce per cubic foot in sandy soils
• Sunburn - Orange/Red/Brown streaks on surfaces facing the point of hottest sun, typically the worst case is around 1-4pm. Sun tolerant species will adapt and grow out of it. Shade loving species may never adapt.

[Palmiz]

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Edited June 23, 2023 by Palmiz

[Palmiz]

2 hours ago, Merlyn said:

CA people might know Archontophoenix better than me, so I couldn't say that there's a specific cause.  There's some brown tips on the older leaves, which might be water, Potassium, Magnesium, or a combo.  The "middle" leaves look fairly good, maybe just a bit wind-tattered.  The "new" leaves coming out with problems might be water, Boron, Manganese, or a combo as well.  It's also possible that there's a bud infection causing some damage, you could try squirting a little household 3% hydrogen peroxide in there.  If it bubbles up there's a fungus in there.

Here's my notes on nutrient deficiencies, it might help figure out what's going on.  Generally a balanced mix palm fertilizer like Florikan or PalmGain is the best bet, and adding small amounts of extra minors as needed.  For example, I have some big Beccariophoenix Alfredii that got yellowed/browned leaf tips over the winter freezes, and I added 2-3 handfuls of Magnesium Sulfate under each canopy because the yellowed ends kept on getting worse this spring.  Adding too much minors can make things worse, because some nutrients are "antagonistic" towards others.  I.e. if you add a huge amount of Manganese then you might induce an Iron or Magnesium deficiency.  So moderation is key!

• Nitrogen - Older fronds turn light green uniformly, new fronds remain dark green until deficiency is really severe
• Potassium - Older fronds get translucent yellow/orange or dead spots on leaves, especially at the tips. Caryota and Arenga get random splotched dead spots in leaves. Sometimes tips are curled or frizzled. Always starts at tips of oldest leaves, moving inwards
• Magnesium -Yellow ends on oldest leaves first, transitions to solid green at the base of each leaf. Does not cause leaf tip necrosis until really severe.
• Iron - Many times caused by overly mucky soil and root rot. Starts with new spear leaves with yellow-green or even white, possibly with spots of green. EDDHA works up to pH of 9, 3-5oz per 100sqft
• Manganese - Lengthwise necrotic streaks in NEW leaves with dead and curled leaf tips. Similar to bands showing Magnesium deficiency. Mn is NOT mobile, so it can't be stolen from old leaves.
• Boron - Bent or necrotic or distorted leaf tips, distorted or bent spear, bands of dead spots on new fans, spears that won't fully open
• Water - Underwatering brown at the edges first, later followed by yellowing of the whole leaf. Overwatering can be drooping fronds turning yellowish and losing color
• Calcium – New leaves are stunted and necrotic, eventually growing only petiole stubs. Deficiency is rare. High pH from adding calcium can induce Magnesium, Manganese, Iron and Boron deficiencies.
• Dolomitic Lime or Azomite - Magnesium Carbonate – reduces acidity/raises pH – slower release and adds Magnesium, helps avoid Potassium deficiencies in Cuban Copernicias. 5Lb per palm on full-size Copernicias and a bit less on Kentiopsis Oliviformis
• Garden Lime - Calcium Carbonate – fast release but works well. 5Lb per palm on full-size Copernicias and a bit less on Kentiopsis Oliviformis
• Sulfur - Elemental sulfur powder or prills reduces pH, 1/2 ounce per cubic foot in sandy soils
• Sunburn - Orange/Red/Brown streaks on surfaces facing the point of hottest sun, typically the worst case is around 1-4pm. Sun tolerant species will adapt and grow out of it. Shade loving species may never adapt.

Thank you @Merlynfor all the information. I will screenshot that info for future help. I will start off with manganese, have to look for some boron and see how that goes first. I'll also try the hydrogen peroxide thing and see if it fizzles. It does get pretty windy where I am at because open field from the school so I get quite a strong breeze going through at times but I think it should handle that. Hope I get all the right amount of things thanks! 🙏 

Izzy

[Merlyn]

1 hour ago, Palmiz said:

Thank you @Merlynfor all the information. I will screenshot that info for future help. I will start off with manganese, have to look for some boron and see how that goes first. I'll also try the hydrogen peroxide thing and see if it fizzles. It does get pretty windy where I am at because open field from the school so I get quite a strong breeze going through at times but I think it should handle that. Hope I get all the right amount of things thanks! 🙏 

Izzy

What are you using for fertilizer now?  Generally a "palm" type fert has a good mix of NPK plus all the minor elements already.  Adding a bunch of random minors may not be a good "fix."  That being said, if it is a Boron deficiency a teaspoon or two of 20 Mule Team Borax in 5 gallons of water is a good treatment.  Just remember that borax is deadly to plants in larger quantities...so less is more!

[Palmiz]

6 hours ago, Merlyn said:

What are you using for fertilizer now?  Generally a "palm" type fert has a good mix of NPK plus all the minor elements already.  Adding a bunch of random minors may not be a good "fix."  That being said, if it is a Boron deficiency a teaspoon or two of 20 Mule Team Borax in 5 gallons of water is a good treatment.  Just remember that borax is deadly to plants in larger quantities...so less is more!

I was using palm gain and now I just purchased wilbur-ellis brand I found at nursery that they said replaced their stock of simplot. I just threw down some manganese sulfate yesterday. The bag I use says it has boron in it. I'll attach a pic of the bag I got. Thanks

[Johnny Palmseed]

1 hour ago, Palmiz said:

I was using palm gain and now I just purchased wilbur-ellis brand I found at nursery that they said replaced their stock of simplot. I just threw down some manganese sulfate yesterday. The bag I use says it has boron in it. I'll attach a pic of the bag I got. Thanks

Take a different picture with the formulation clearly displayed. That will tell the percentage of each micro nutrient.

[Palmiz]

1 hour ago, Johnny Palmseed said:

Take a different picture with the formulation clearly displayed. That will tell the percentage of each micro nutrient.

I'll get it when I get home. Weird that on my phone I can read it but not when I post it on thread. 👍Thanks

[Palmiz]

10 minutes ago, Palmiz said:

I'll get it when I get home. Weird that on my phone I can read it but not when I post it on thread. 👍Thanks

Nevermind forgot I threw bag away and put fertilizer in container 🤣 i wrote it out and took pic

[Merlyn]

The micros in the new fertilizer seem totally reasonable, as long as they are in "bioavailable forms."  The NPK ratio is different from the PalmGain formulation, but that 2:1:3 ratio was experimentally derived for Florida's sandy soils, not CA.  Local CA people may know a lot better about what ratios work the best out there.  If I had to guess, I'd think that your soil is higher pH, and that might be contributing to the issues:

So if your soil is relatively high pH (7.5-8.5 or so) then the palms may not be able to absorb Iron, Manganese, Boron, Copper and Zinc.  Adding a little supplemental EDDHA Iron or those other micros is probably a good idea. 

On Boron, note the 0.06% ratio is really low.  In a 50lb bag there's only 0.5oz of Boron.  That's usually plenty as a supplement, because most of the time palms are planted with mulch or other decomposing matter around them.  So the natural decomposition provides plenty of Boron.  In FL it's sometimes an issue because our torrential thunderstorms wash all the Boron away really fast.  In your case you've got gravel/rock and keep the area clean and tidy so there's not a good natural source of Boron.  The EDIS/IFAS/UFL link I posted earlier suggests 2-4oz of Borax in 5 gallons of water per palm.  I'd be inclined to do 1oz in 5 gallons on all of your palms, and repeat in a couple of months.  It may take 6 months to a year for everything to grow out nice again.

[Palmiz]

9 hours ago, Merlyn said:

The micros in the new fertilizer seem totally reasonable, as long as they are in "bioavailable forms."  The NPK ratio is different from the PalmGain formulation, but that 2:1:3 ratio was experimentally derived for Florida's sandy soils, not CA.  Local CA people may know a lot better about what ratios work the best out there.  If I had to guess, I'd think that your soil is higher pH, and that might be contributing to the issues:

So if your soil is relatively high pH (7.5-8.5 or so) then the palms may not be able to absorb Iron, Manganese, Boron, Copper and Zinc.  Adding a little supplemental EDDHA Iron or those other micros is probably a good idea. 

On Boron, note the 0.06% ratio is really low.  In a 50lb bag there's only 0.5oz of Boron.  That's usually plenty as a supplement, because most of the time palms are planted with mulch or other decomposing matter around them.  So the natural decomposition provides plenty of Boron.  In FL it's sometimes an issue because our torrential thunderstorms wash all the Boron away really fast.  In your case you've got gravel/rock and keep the area clean and tidy so there's not a good natural source of Boron.  The EDIS/IFAS/UFL link I posted earlier suggests 2-4oz of Borax in 5 gallons of water per palm.  I'd be inclined to do 1oz in 5 gallons on all of your palms, and repeat in a couple of months.  It may take 6 months to a year for everything to grow out nice again.

Thanks so much for more useful info. I never tested the pH of my soil, I will need to get that tested to see. I'll  also start with the borax treatment to see if I get any changes. I was wondering if it will affect the small palms planted all around the area of the kings also. Thank you so much Arthur! I really appreciate it!