Mule Recovery

[Manalto]

Last winter didn't seem any worse than the previous few, and yet damage to my mule palm was extensive. Because of this, I would consider the mule palm as marginal in zone 8B. It's my understanding that fronds should be left on the plant until completely brown because there is nutrient uptake until that point. As usual, I erred on the side of caution (i.e., procrastinated), and performed nine frondectomies, certain that they were good and dead.

 

The remaining leaves have considerable damage. Only the two that emerged this year are solid green.

It looks like it's going to be a long recovery if we don't have another winter like the last one!

[RJ]

Curious to what your temps were? I can say that mules vary widely with hardiness. The one I planted at my folks house is definitely more leaf hardy than a large CIDP planted just down the road.  That being said, I agree that mule palms in general should be considered a 8b palm at minimum. They’re  quite resilient at coming back and fast growth makes them suitable for the few times they do get fried. Disclaimer: this applies to hot (humid) climates obviously places like the UK and PNW this probably doesn’t apply. 

[Manalto]

21 hours ago, RJ said:

Curious to what your temps were. I can say that mules vary widely with hardiness. The one I planted at my folks house is definitely more leaf hardy than a large CIDP...

The lowest temperatures were 23° and 19° on two consecutive nights in mid January. Maybe it was the extended cold that caused the damage? (Because it has gone down to 17° previously with no damage at all.) My Livistona chinensis was also hit pretty hard, as were others in town.  As you mentioned in your area, we also lost a couple of large CIDPs.

[MarcusH]

7 minutes ago, Manalto said:

The lowest temperatures were 23° and 19° on two consecutive nights in mid January. Maybe it was the extended cold that caused the damage? (Because it has gone down to 17° previously with no damage at all.) My Livistona chinensis was also hit pretty hard, as were others in town.  As you mentioned in your area, we also lost a couple of large CIDPs.

Can I see a picture of the trunk ? Does it have green or burgundy boots ? 

[RJ]

11 hours ago, Manalto said:

The lowest temperatures were 23° and 19° on two consecutive nights in mid January. Maybe it was the extended cold that caused the damage? (Because it has gone down to 17° previously with no damage at all.) My Livistona chinensis was also hit pretty hard, as were others in town.  As you mentioned in your area, we also lost a couple of large CIDPs.

I wouldn’t think those temps would do anything significant to a mule. The fact that you lost CIDP indicates to me that it must of been the duration of the cold, CIDP I have found to be very bud hardy, much like L chinensis. Asume it at least go above freezing. 

[Manalto]

On 6/24/2024 at 9:28 AM, MarcusH said:

Can I see a picture of the trunk ? Does it have green or burgundy boots ? 

Sorry for the delayed response. Are those with green boots known to be more/less hardy?

 

[RJ]

1 hour ago, Manalto said:

 

Sorry for the delayed response. Are those with green boots known to be more/less hardy?

 

Jury is out. Many more pieces to the puzzle than that, unfortunately. 

[MarcusH]

4 hours ago, Manalto said:

Sorry for the delayed response. Are those with green boots known to be more/less hardy?

 

From our research the ones with the green boots have more Queen palm traits so supposedly they should be less hardy . 

We asked a few members of this forum to post their mule palms on here as well as giving us some information about their leaf hardiness.  

So far the ones with the burgundy boots are more cold hardy and the ones with the green boots less . 

A nursery guy in Jacksonville Florida came up with those facts . We're just investigating further. 

 

[happypalms]

 Nice  palm it looks like it will recover well considering it has got to live that long and get to a healthy size.

[Manalto]

14 hours ago, MarcusH said:

From our research the ones with the green boots have more Queen palm traits so supposedly they should be less hardy.

Makes sense, especially if the reporting bears out the assumption.

The seller (Mule Palms of Mississippi) was proud of the cold hardiness of both parent plants; the Syagrus is supposedly var. littoralis, if that means anything.  The reason my mule got hit so hard is a bit of a head-scratcher. 

[Fusca]

1 hour ago, Manalto said:

Makes sense, especially if the reporting bears out the assumption.

The seller (Mule Palms of Mississippi) was proud of the cold hardiness of both parent plants; the Syagrus is supposedly var. littoralis, if that means anything.  The reason my mule got hit so hard is a bit of a head-scratcher. 

The litoralis variant of Syagrus romanzoffiana is supposedly more cold hardy but I don't think it's been proven.  There seems to be variation within the species but perhaps not as much as with Butia.  Yours is a good example of this - it seems to have more Butia with the burgundy colored leaf boots and yet it suffered damage at higher temperatures than expected.  We can't make too many assumptions with these because there's so much variation involved in the cross.

[Manalto]

3 hours ago, Fusca said:

The litoralis variant of Syagrus romanzoffiana...

Oops, one "T" in litoralis. Hey, at least I italicized. 😏

I suspected that hardiness was more complicated than merely the physical characteristics of Syagrus vs. Butia. I'm just disappointed that, after achieving a respectable landscape presence, it has shown to be vulnerable here in some winters. I suppose a back-cross with Butia would help - if that's even possible, since we're talking about a mule!

[DAVEinMB]

@Manalto you got a combination of burgundy boots and plumose fronds. Burgundy boots would be indicative of butia as stated above and plumose fronds lean on the queen side at least from what I've seen. It's a gorgeous palm even in it's current recovery state. Keep us updated

[Fusca]

On 6/23/2024 at 10:23 AM, Manalto said:

It's my understanding that fronds should be left on the plant until completely brown because there is nutrient uptake until that point. 

It looks like it's going to be a long recovery if we don't have another winter like the last one!

Yes, it's best to leave the yellowing/partially green fronds on the palm until completely brown especially while it's in recovery.  If it grows fast like the majority of mules you'll be pleasantly surprised how quickly it recovers a full crown.  In February 2021 I lost a large mule smaller than yours (7 years from a 3-gal) to 9°F and 13°F in consecutive nights but a smaller mule next to it (3 years from a strap-leaf seedling) survived after a trunk cut.  The survivor grew to perhaps a foot shorter overall height after one season of growth and almost looked like nothing happened.  Neither was protected.  Interestingly the one that died was larger, had more Butia traits (burgundy leaf boots and not as fast - still fast...).  Doesn't make sense but goes to show the unpredictability.  🤷‍♂️

[RJ]

31 minutes ago, Fusca said:

Yes, it's best to leave the yellowing/partially green fronds on the palm until completely brown especially while it's in recovery.  If it grows fast like the majority of mules you'll be pleasantly surprised how quickly it recovers a full crown.  In February 2021 I lost a large mule smaller than yours (7 years from a 3-gal) to 9°F and 13°F in consecutive nights but a smaller mule next to it (3 years from a strap-leaf seedling) survived after a trunk cut.  The survivor grew to perhaps a foot shorter overall height after one season of growth and almost looked like nothing happened.  Neither was protected.  Interestingly the one that died was larger, had more Butia traits (burgundy leaf boots and not as fast - still fast...).  Doesn't make sense but goes to show the unpredictability.  🤷‍♂️

Starting to think that “traits” don’t equate to less hardy or more hardy. 

[Fusca]

2 hours ago, RJ said:

Starting to think that “traits” don’t equate to less hardy or more hardy. 

Agree.  Or speed for that matter.  I got a 3-gal mule from MPOM last year that looked exactly like a small queen.  I expected it to take off like a rocket this year but it hasn't done much yet.  Maybe it's still working on its roots and will blast off later?

[RJ]

8 minutes ago, Fusca said:

Agree.  Or speed for that matter.  I got a 3-gal mule from MPOM last year that looked exactly like a small queen.  I expected it to take off like a rocket this year but it hasn't done much yet.  Maybe it's still working on its roots and will blast off later?

The genetic lottery is so complicated, especially in any hybrid. I had this discussion with patrix a few years ago regarding his  3 way crosses. He said the options for outcomes , regarding appearance are so complex that it’s almost impossible to tell what the end result will be. I’ve got two mule x yatay crosses that look entirely different. 

[Fusca]

37 minutes ago, RJ said:

The genetic lottery is so complicated, especially in any hybrid. I had this discussion with patrix a few years ago regarding his  3 way crosses. He said the options for outcomes , regarding appearance are so complex that it’s almost impossible to tell what the end result will be. I’ve got two mule x yatay crosses that look entirely different. 

Yes, exactly.  Makes the growing more interesting not knowing what you are going to end up with!  I bet your yatay mules were crossed with the same two palms at the same time too!  I suppose it's a bit of a gamble for cold hardiness in marginal zones but worth it in my opinion.  I haven't seen many hybrids that weren't nice looking. 

[RJ]

The only mules that I’m aware of, that have ever been able to be crossed are the two a Huntington botanical garden in CA, they’re huge mules that DR. Wilcox made. Every giant mule a dick Douglas’s garden was sterile , and IIRC all the old ones were from Dr. Wilcox. 
 

 

[MarcusH]

On 6/27/2024 at 12:30 PM, Fusca said:

The litoralis variant of Syagrus romanzoffiana is supposedly more cold hardy but I don't think it's been proven.  There seems to be variation within the species but perhaps not as much as with Butia.  Yours is a good example of this - it seems to have more Butia with the burgundy colored leaf boots and yet it suffered damage at higher temperatures than expected.  We can't make too many assumptions with these because there's so much variation involved in the cross.

Very true there's always an exception to it but from the research we were doing it shows that the ones with burgundy colored boots were more leaf and cold hardy compared to the others with green boots.  There's an exception to everything but the boot colors are a pretty good indicator to determine which one is more cold hardy.  

Queen palms cold hardiness vary widely. Some can survive well below 20F while some others get fried somewhere between 20 to 23F . 

It could be that his Mule palm was mixed with a less cold hardy Queen palm. Just a theory. 

 

[MarcusH]

On 6/23/2024 at 10:23 AM, Manalto said:

Last winter didn't seem any worse than the previous few, and yet damage to my mule palm was extensive. Because of this, I would consider the mule palm as marginal in zone 8B. It's my understanding that fronds should be left on the plant until completely brown because there is nutrient uptake until that point. As usual, I erred on the side of caution (i.e., procrastinated), and performed nine frondectomies, certain that they were good and dead.

 

The remaining leaves have considerable damage. Only the two that emerged this year are solid green.

It looks like it's going to be a long recovery if we don't have another winter like the last one!

Speaking of zones I agree with you on the zone rating. We're in zone 9a ( realistically 8b) in SA. There were Mule palms planted near our zoo . All Mule palms had severe leaf damage and it only got down to 19F last winter.  For ever green experience I would say Mules are best to grow in areas where temps don't go below 20F. Below that the leafes start to burn in most cases. 

[Dartolution]

On 6/27/2024 at 10:26 AM, Manalto said:

Makes sense, especially if the reporting bears out the assumption.

The seller (Mule Palms of Mississippi) was proud of the cold hardiness of both parent plants; the Syagrus is supposedly var. littoralis, if that means anything.  The reason my mule got hit so hard is a bit of a head-scratcher. 

@Manalto Mine also came from MPOP, but is potted. This past winter we had an ultimate low of 10F here, and it remained outside, no supplemental heat. 

I just laid mine on the ground, and threw a bedsheet/frostcloth over it. 

Tip burn, no spear pull, no other damage. SO, just goes to show how variable the mules really are. 

 

I KNOW that duration of cold is the #1 factor in their winter survivability/extent of damage. 

Just likely was a bad season. Here's to better winters! 

[DAVEinMB]

I mean I'll still say that mule palms are a fairly safe bet for 8b, especially a warm 8b. You're gonna roll the dice but not to the same extent as some other zone pushing palms.  I have 5 in different spots in my yard and have had different post winter outcomes... and yea siting plays a role as we all know. I've had to trunk cut one, nurse one a bit and salute the other three for their service lol. I've seen temps in the mid to low teens and one of my mules hasn't shown any signs of distress, but this is not always the case. Yes they are variable being a hybrid but don't discount their resilience.