Syagrus sancona in zone 10a-10b

[idontknowhatnametuse]

I have this Syagrus sancona seedling in Monterrey, Mexico. I am between zones 10a and 10b. Planning to put it in the ground next year in the spring. Has anyone else grown this species in these zones?

[Merlyn]

@idontknowhatnametuse a quick look at KinzyJr's spreadsheet of hardiness reports shows it should be fine.  I have some seedlings about that size that I plan to use here in 9b/9a borderline.  It looks like they are ok above freezing, take some leaf burn around 27-28 and might die at 24-25.

[mnorell]

I have one of these in the Palm Springs area, zone 10a low desert, in the ground with northeasterly exposure and very little winter sun. Has seen roughly 32-33F at ground level with no issues. Far more problems with summer sun accompanied by daytime highs as high as 124F. This year was the most brutal in about 100 years of record-keeping at Palm Springs, and every day hit the 110s for months. My in-ground test subject, about two-gallon size and now pinnate, had relatively little issue with sun/heat-burn in 2023, but this year it really took a beating cosmetically, though it is still healthy. Winter caused it no real issues and we "usually" are around 38-44F at dawn and somewhere 64-74 for a high in the two coldest months, December and January. My other test subjects are all in pots in more protected areas (part sun/shade) and they have no issue whatsoever winter or summer.

I think the issue with S. sancona is that the foliage, which is much lighter, glossier and supple as compared to other species in the genus, is just more delicate, at least when young and if under open sky. A larger S. x montgomeryana "Coco Queen" just a few feet away from my in-ground S. sancona has shown no discomfort from extreme heat/sun-exposure to 124F, nor from cold...a much tougher plant with thicker, darker lamina. I also have several young Attalea cohune planted nearby, and that species is like S. x montgomeryana in being much tougher in the summer heat/sun (no damage whatsoever), although while young it does suffer some leaf-burn in winter cold if under open sky (low 30s F) where the nearby S. sancona strangely enough doesn't seem to have that problem.

I think Merlyn's suggested temp range seems logical out west where it's dry, but perhaps a little optimistic for Florida or where wet freezes occur. I'm assuming that due to your elevation you have a more intermediate type of winter profile in terms of the quality of cold-waves? When I look at Monterrey's climate on Weatherspark, it appears to me that your averages are good, but Wikipedia shows that the weather station for Monterrey has experienced heat as high as 118F and cold down to 18.5F? Hopefully your specific location is warmer in winter, as it doesn't seem this species would survive below about 25F in any sort of humid cold.

Jim Denz in Los Altos Hills (north-central California) has written that S. sancona has done fine in his quite cool winters as low as 26F with some spotting and tip-burn. Gyuseppe in Napoli (Italia) wrote that his died at 28.4F in his somewhat chillier-winter climate. Eric Schmidt at Leu Gardens in Orlando has stated that S. sancona suffered minor burn in 2010 at 29F but survived. Taking those anecdotal experiences into account, and if you think you'll stay long-term above mid-20s F, I would guess you would be guardedly safe to plant it, though I would suggest you give it at least some sort of canopy, plus north-wind shielding, for protection, and allow that you might lose it in an extreme winter.

[idontknowhatnametuse]

4 hours ago, mnorell said:

I have one of these in the Palm Springs area, zone 10a low desert, in the ground with northeasterly exposure and very little winter sun. Has seen roughly 32-33F at ground level with no issues. Far more problems with summer sun accompanied by daytime highs as high as 124F. This year was the most brutal in about 100 years of record-keeping at Palm Springs, and every day hit the 110s for months. My in-ground test subject, about two-gallon size and now pinnate, had relatively little issue with sun/heat-burn in 2023, but this year it really took a beating cosmetically, though it is still healthy. Winter caused it no real issues and we "usually" are around 38-44F at dawn and somewhere 64-74 for a high in the two coldest months, December and January. My other test subjects are all in pots in more protected areas (part sun/shade) and they have no issue whatsoever winter or summer.

I think the issue with S. sancona is that the foliage, which is much lighter, glossier and supple as compared to other species in the genus, is just more delicate, at least when young and if under open sky. A larger S. x montgomeryana "Coco Queen" just a few feet away from my in-ground S. sancona has shown no discomfort from extreme heat/sun-exposure to 124F, nor from cold...a much tougher plant with thicker, darker lamina. I also have several young Attalea cohune planted nearby, and that species is like S. x montgomeryana in being much tougher in the summer heat/sun (no damage whatsoever), although while young it does suffer some leaf-burn in winter cold if under open sky (low 30s F) where the nearby S. sancona strangely enough doesn't seem to have that problem.

I think Merlyn's suggested temp range seems logical out west where it's dry, but perhaps a little optimistic for Florida or where wet freezes occur. I'm assuming that due to your elevation you have a more intermediate type of winter profile in terms of the quality of cold-waves? When I look at Monterrey's climate on Weatherspark, it appears to me that your averages are good, but Wikipedia shows that the weather station for Monterrey has experienced heat as high as 118F and cold down to 18.5F? Hopefully your specific location is warmer in winter, as it doesn't seem this species would survive below about 25F in any sort of humid cold.

Jim Denz in Los Altos Hills (north-central California) has written that S. sancona has done fine in his quite cool winters as low as 26F with some spotting and tip-burn. Gyuseppe in Napoli (Italia) wrote that his died at 28.4F in his somewhat chillier-winter climate. Eric Schmidt at Leu Gardens in Orlando has stated that S. sancona suffered minor burn in 2010 at 29F but survived. Taking those anecdotal experiences into account, and if you think you'll stay long-term above mid-20s F, I would guess you would be guardedly safe to plant it, though I would suggest you give it at least some sort of canopy, plus north-wind shielding, for protection, and allow that you might lose it in an extreme winter.

The only place where it really gets cold in Monterrey is in the peaks of the mountains surrounding the city. The city is much more warmer than the mountains. Especially the lower parts.

[rizla023]

I am growing in 10b, Santa Ana, CA and mine is growing well. 

[mnorell]

1 hour ago, idontknowhatnametuse said:

The only place where it really gets cold in Monterrey is in the peaks of the mountains surrounding the city. The city is much more warmer than the mountains. Especially the lower parts.

Where do you think the temperature records listed on Wikipedia originate? Would you say you think these are extremes that have been experienced in the city itself or in some specific weather station outside of town? Here in the USA these records are usually reflecting airports where sensors are out in an open field and not indicative of what most urban or suburban homes experience. But I wonder how this typically (or historically) has worked in Mexico.

[idontknowhatnametuse]

1 hour ago, mnorell said:

Where do you think the temperature records listed on Wikipedia originate? Would you say you think these are extremes that have been experienced in the city itself or in some specific weather station outside of town? Here in the USA these records are usually reflecting airports where sensors are out in an open field and not indicative of what most urban or suburban homes experience. But I wonder how this typically (or historically) has worked in Mexico.

It's in airports too