Suffering little king palms

[Jeremy Borum]

I planted 6 little king palms in August, thinking they would have lots of time to establish themselves before the hot summer weather in Los Angeles hit. I see them all over town and they're usually quite happy. It's now May and they look far worse than when I bought them. It could just be my fault, but I think there's something else happening too.

My main concern is the black stuff spreading along the trunk and stems and the spots in the leaves. Both of those seem like bad signs, but I don't know what they mean.  In one of the photos you can see that it wipes off easily where my finger is, but it's very thick.

The leaves are all yellowing, but that may be a simple lack of water. I was very good about watering them through the fall to help them get established. In winter it got cooler and occasionally rainy so I didn't need to worry about it as much.  For most of this year they've gotten water probably once a week or whenever it rained. Now that I'm researching it, I gather that's insufficient.

They were previously in full sun. I fertilized them a couple weeks ago and rolled the big pot under a tree so they could recover in relative safety for a while.

I'll fertilize a few times a year now and water every couple days, but the spreading black stuff and leaf spots still seem like a problem. I'd appreciate any advice you have.

The last photo (with the large palm) is how they used to look 9 months ago when I first planted them.

Many thanks.

 

[JLM]

Looks like a fungal disease, i would look into treatments for fungal diseases. @kinzyjr i feel like you would know what this is and if it is fungal, how to treat it.

[kinzyjr]

@Jeremy Borum

Do you happen to know which species of King it is?

The brown spots on the leaves look similar to some of the fungal spotting I've seen, but I thankfully haven't had to deal with any of the black fungus.  A good test to do is to pour some hydrogen peroxide down the crown and fizzes up.  If it does, there is some microbe problem.

[rprimbs]

Definitely a fungal disease.  My palms -- that don't have good drainage, and get too much water -- have those same symptoms.  It doesn't seem to kill them but it definitely slows them down.  In addition to watering a little less you might try fertilizing a little more.  I don't know why buy sometimes extra fertilizer -- like Nutricote with minors -- seems to help.

[Jim in Los Altos]

15 hours ago, rprimbs said:

Definitely a fungal disease.  My palms -- that don't have good drainage, and get too much water -- have those same symptoms.  It doesn't seem to kill them but it definitely slows them down.  In addition to watering a little less you might try fertilizing a little more.  I don't know why buy sometimes extra fertilizer -- like Nutricote with minors -- seems to help.

Good advice for many palms but never consider watering a king palm less. They are nearly aquatic in there water needs. In fact, of the fifty I have in my garden, five are growing very happily in year round pond water. All their roots are under water. It’s impossible to over water them but very easy to underwater them. 

Here’s one of them with its roots all under water. 

Edited April 25, 2020 by Jim in Los Altos

[rprimbs]

6 hours ago, Jim in Los Altos said:

Good advice for many palms but never consider watering a king palm less. They are nearly aquatic in there water needs. In fact, of the fifty I have in my garden, five are growing very happily in year round pond water. All their roots are under water. It’s impossible to over water them but very easy to underwater them. 

Here’s one of them with its roots all under water. 

How do you water your palms?  I am using the dripper tubing with the built in emitters.   Maybe I am watering too close to the trunk.

[GottmitAlex]

6 hours ago, Jim in Los Altos said:

Good advice for many palms but never consider watering a king palm less. They are nearly aquatic in there water needs. In fact, of the fifty I have in my garden, five are growing very happily in year round pond water. All their roots are under water. It’s impossible to over water them but very easy to underwater them. 

Here’s one of them with its roots all under water. 

Magnificent Jim!

Wooooow!  Thanks for the pics.

[Steve Mac]

Jeremy, Looks to me like sooty mould (or mold)  Google that mate.

[DoomsDave]

@Jeremy Borum, nice to meet you!

Looks like you have common Kings, Archontophoenix cunninghamiana. If you got them from most retail nurseries around these parts, I'm almost certain that's what they are. There are other species of "Archies" as well.

Thanks for sharing the picture of the situation the palms are in.

Based on that, I'll offer some advice:

Kings are thirsty, oh yes, as @Jim in Los Altos pointed out, and I vigorously concur. I love them anyway.

That looks like a mature king right behind your wall in your last picture in your neighbor's yard. I'd strongly suggest, if you can, planting them in the ground. They're big things and keeping them in the pots will stunt them. Also, if they get tall enough in the pot, or box that may tip over if it gets windy. If the wind blows just right, it might topple into your pool.

If you really want to have palms in a pot and not in the ground, I'd respectfully suggest another species. If you like the multi-trunk look, consider a "Golden Cane Palm" or Dypsis lutescens. They're much better suited scale-wise for your situation and they're multi-trunking types. They're readily available around these parts. There's other clumping Dypsis species, too. Another possibility is the Solitaire Palm, Ptychosperma elegans, from Australia. It makes a great pot plant, both for indoor and outdoor plant-scapes. Max diameter on the trunks is about three inches across. They're single trunkers, but you could put, say, about four in your box.

Whatever species you decide to grow in a pot or box, remember that you will need to replace the potting soil periodically. The high-humus mixes lose most of their volume over time as the humus decays. The good news is that repotting with new dirt helps a lot.

If you have any further questions, do please ask. I'm honestly not much at dealing with the fungus issues you appear to have, though I've been successful with the peroxide treatment a number of times.

[Jim in Los Altos]

On 4/25/2020 at 6:39 PM, rprimbs said:

How do you water your palms?  I am using the dripper tubing with the built in emitters.   Maybe I am watering too close to the trunk.

Water around King palms trunks is okay. Some of the trunks on mine have water touching them year round. This doesn’t apply to all palm species though of course. But make sure the soil further out from your palm’s trunks gets water as well. If you’re using drip irrigation, there should be emitters scattered beneath the drip line area of your palms. I prefer spray irrigation since it distributes water everywhere there are roots present and keeps my understory bromeliads and other plants moist. 

Edited April 27, 2020 by Jim in Los Altos

[Jeremy Borum]

On 4/26/2020 at 10:43 AM, DoomsDave said:

I'd strongly suggest, if you can, planting them in the ground. They're big things and keeping them in the pots will stunt them.

Thanks Dave. I'm renting this place and growing as much as I can in pots while I'm here. It's basically my nursery, and I hope to put almost everything in the ground when I buy a place of my own. The huge rolling planter pot is large enough to give them several good years of unfettered growth, so I won't be worried about stunting their growth for quite a while. The top is 3 ft square, so it's a monster, and the full size palm you thought was in a neighbor's yard was actually in the same pot before it died. If I can get these little palms to live long enough that the planter size is an issue I'll be very happy!

 

On 4/25/2020 at 7:06 PM, gtsteve said:

Jeremy, Looks to me like sooty mould (or mold)  Google that mate.

Thanks Steve. I already suspected something like that and sprayed it with Neem oil, but I'll do a bit more research.

[Jeremy Borum]

Many thanks all.

My little king palms aren't doing great and I need to cut off a bunch of dead stuff, but the progress of the sooty mold seems to have stopped. I'm not sure, but I *think* some new spikes are trying to open from 4 out of the 6, so they're struggling but not lost. (Yet.) The shady spot definitely seems to help for now, so I won't put them back in the sunny corner by my pool until they look vigorous and happy again.

Your advice was much appreciated.

[Jeremy Borum]

Hello everybody,

I've had these palms a year an a half now, and I haven't yet figured out what they need from me. They seem to die as fast as they grow and I can't keep the sooty black fungus or brown spots away. I presume the spotting is a nutrition problem, but I've read I shouldn't fertilize much during the more dormant season. It's not practical for me to spray all of the surface area with copper fungicides every few months, nor cheap if that's what's required.  Since moving them to this more shady spot I've been trying to give them water 2-3 times per week.

What am I doing wrong? 

[James B]

Based on what I see these are A.Cunninghamiana. I do not see a fungal problem, I see sun burn. Especially when young the common King Palm never looks good in direct afternoon sun. So since you have options make sure any sun they get is in the morning. The yellowing is from too much sun plus it’s winter. If you are going to keep them in a container make sure to water them every other day and when it warms up move to watering every day. Come March give them fertilizer and they should green up with the consistent watering. If they don’t, they are easy to find a replacement. You can cut your losses and remove them. 

[James B]

If your yard gets intense sun, you can always try A.Alexandrae or A.Maxima. Both look better in sun than the common King.

Edited January 10, 2021 by James B

[Silas_Sancona]

1 hour ago, James B said:

Based on what I see these are A.Cunninghamiana. I do not see a fungal problem, I see sun burn. Especially when young the common King Palm never looks good in direct afternoon sun. So since you have options make sure any sun they get is in the morning. The yellowing is from too much sun plus it’s winter. If you are going to keep them in a container make sure to water them every other day and when it warms up move to watering every day. Come March give them fertilizer and they should green up with the consistent watering. If they don’t, they are easy to find a replacement. You can cut your losses and remove them. 

Agree w/ James.. Effects from the sun are very obvious in picture # 3.. Esp. on the center stalk, closer to the base. Pic #4 shows the natural tomentum ( fuzz ) these can have on newer leafstalks, before it has been rubbed off..

Would follow his advise on watering/ feeding once spring warmth returns.

[Jeremy Borum]

I'm fairly certain these are indeed Archontophoenix Cunninghamiana, because the underside is purely green and those little hairs are present. Are young ones particularly sensitive to sun? I see them all over my city in full sun, and they generally look healthy. Sunburn feels like a wrong diagnosis to me because I've been sheltering them underneath this pine tree for 8 months now, but they do get a bit of direct sun in the late afternoon.

I've also read that they're generally fast growers, but mine aren't living up to that reputation yet.

My hope is that they'll one day be very happy in full sun all day long, because my intention was to have them proudly in the corner of my yard by my pool, not hiding under a pine tree.

[Jim in Los Altos]

15 minutes ago, Jeremy Borum said:

I'm fairly certain these are indeed Archontophoenix Cunninghamiana, because the underside is purely green and those little hairs are present. Are young ones particularly sensitive to sun? I see them all over my city in full sun, and they generally look healthy. Sunburn feels like a wrong diagnosis to me because I've been sheltering them underneath this pine tree for 8 months now, but they do get a bit of direct sun in the late afternoon.

I've also read that they're generally fast growers, but mine aren't living up to that reputation yet.

My hope is that they'll one day be very happy in full sun all day long, because my intention was to have them proudly in the corner of my yard by my pool, not hiding under a pine tree.

They’ll do fine in full sun particularly since you have a group of them ant they tend to “protect” each other from dry wind and hot sun. The ones I gave in full all day sun are happy. The nicest ones, however, are in partial shade. Just keep them really well watered. 

[Bazza]

Jeremy......I hope that little blue watering can isn't what you're using to water your palms.

You really need to use a hose hooked up to a regular water spigot - or bib - to give them enough irrigation.

Those planters should be soaked and saturated each watering. Sometimes when I water my potted plants I even go back and forth several times repeating the soaking just to make sure I get water distributed to as much of the root system as possible.

There are so many variables involved in proper watering of potted material including drainage and potting media I'm not even going into but just emphasizing how important it is to get that planter saturated fully each watering.

Also - whenever any of my potted material looks a little "weak" - I hit them with my Miracle Grow Liqui-feed hose end feeder and continue once a week liquid feedings until I see a proper response.

I'm in Florida so take this advice with a grain of salt because obviously your climate is a little different - but - adequate fertilizing is one of the most misunderstood aspects of plant culture in my experience.  Using a liquid feed like this MG system is one of the easiest and most fool proof methods of addressing any issues in an expeditious manner.

Just my 2 cents.....hth!

 

[NOT A TA]

12 minutes ago, Bazza said:

Jeremy......I hope that little blue watering can isn't what you're using to water your palms.

You really need to use a hose hooked up to a regular water spigot - or bib - to give them enough irrigation.

I thought the same thing! Would need to make a lot of trips with that watering can. AND, in the pic from past summer the other plant in the box looks awfully dry.

[Jeremy Borum]

I typically water thoroughly with a hose, but I'll try to give them even more regular water. Maybe that simple solution is all I need. 

The nasturtiums that were also in the pot sprout in winter and die completely in summer, so their dryness isn't indicative of anything. 

Thanks all for your help, it's much appreciated. 

[doubravsky]

Cunninghamias inland do suffer in full sun when young, and the leaf browning is pretty typical. Be patient and keep up the water... and they will acclimate to the sun in a few years and look great.