Reference: Agave Hardiness

[Gafoto]

I'm happy to report that Ovatifolia and Bella made through our 6A winter. It got to minus zero one night, and we had some periods were the temps were in the teens, but, overall, not a bad winter for us. Of course, both plants were sheltered from snow and moisture, ( not in pots ), so they had help. The big Ovatifolia is even showing an emerging pup. The gamble now is when to remove the protection. Spring can bring almost the entire 4 seasons of weather here, but, usually late May is safe.

How did you shelter the ovatifolia? I live in Salt Lake and the concern I have is finding some kind of shelter that will withstand heavy snow. Also the ovatifolia I’m planting will eventually get pretty huge and be challenging to cover up. I see plenty of parryi and havardiana around but I have yet to see other agave.

[jnewmark]

I'm happy to report that Ovatifolia and Bella made through our 6A winter. It got to minus zero one night, and we had some periods were the temps were in the teens, but, overall, not a bad winter for us. Of course, both plants were sheltered from snow and moisture, ( not in pots ), so they had help. The big Ovatifolia is even showing an emerging pup. The gamble now is when to remove the protection. Spring can bring almost the entire 4 seasons of weather here, but, usually late May is safe.

How did you shelter the ovatifolia? I live in Salt Lake and the concern I have is finding some kind of shelter that will withstand heavy snow. Also the ovatifolia I’m planting will eventually get pretty huge and be challenging to cover up. I see plenty of parryi and havardiana around but I have yet to see other agave.

Since Winters here can get pretty harsh, sometimes with freezing rains, followed by single digit temps, I built a 4 sided cube with 1x6 boards that I position around the plant. I can stack on additional layers when and if the plants grow larger. The " box " is insulated on the inside with foam board, and I place an old storm window on the top. That's for the Ovatifolia in the ground. I also have a raised bed, about two feet tall, that is 4Ft by 6 ft, filled with mostly limestone gravel and coarse sand, where I grow Winter hardy cactus, and some of the smaller Agaves like the Bella. I put a " hoop house " cover over it in Winter, with 6 mil clear poly. I have had no luck with any of the so called " Winter hardy " Agaves, except Bella and Ovatifolia; we just get too much moisture, year round here. The cactus don't seem to mind, but its too much for the Agaves like Parryi and Utahensis. Good luck ! I should add, I've had some luck with Agave Funkiana also, but, after a couple of years, they are showing signs of rot, now.

[abborean]

Sorry to read about your funkiana. I've been bragging about your success with them there! Have them trialing in south Jersey where they are doing well as far as I know. Let me know if you want more to try different locations and microclimates around your place.

[jnewmark]

Sorry to read about your funkiana. I've been bragging about your success with them there! Have them trialing in south Jersey where they are doing well as far as I know. Let me know if you want more to try different locations and microclimates around your place.

Thanks for that. I am really puzzled about Funkiana, they were doing great. I checked them in Febuary and they showed no signs of distress. Then, last month, we had some very rainy, then sunny days. I'm wondering if the condensation that forms on the glass inside, dripped on to the core of the plants, and they started to rot ? All three plants are showing signs of rotting now. The large Ovatifolia ( first year in the ground ) right next to the larger Funkiana, came through with flying colors.

[abborean]

Don't think I can give away funkiana here. Brought home almost all of them from the plant sale this weekend unsold. Be glad to send you a few gratis.

[jnewmark]

Don't think I can give away funkiana here. Brought home almost all of them from the plant sale this weekend unsold. Be glad to send you a few gratis.

That would great ! Do you still have my address ?

[abborean]

Could probably find it in our PMs but resend to make it easier. Will go out next week.

[jnewmark]

Could probably find it in our PMs but resend to make it easier. Will go out next week.

PM sent. Thanks !

[jnewmark]

I should add that Agave bracteosa has survived in my covered, raised bed outside. Very surprising as it is a Zone 7B plant. It has out lived every Utahensis and Parryi I have ever tried outside in that bed.

[Meangreen94z]

I should add that Agave bracteosa has survived in my covered, raised bed outside. Very surprising as it is a Zone 7B plant. It has out lived every Utahensis and Parryi I have ever tried outside in that bed.

Yes, bracteosa is among the hardiest for wet climate cold. The large specimen I saw outside a local nursery appeared to take no damage from temperatures in the 3-6°F range.

[jnewmark]

I should add that Agave bracteosa has survived in my covered, raised bed outside. Very surprising as it is a Zone 7B plant. It has out lived every Utahensis and Parryi I have ever tried outside in that bed.

Yes, bracteosa is among the hardiest for wet climate cold. The large specimen I saw outside a local nursery appeared to take no damage from temperatures in the 3-6°F range.

Any other cold, wet tolerant Agaves you might know of ? I'm thinking I could bump up a Zone, seeing as how Bracteosa is doing so good here.

[westfork]

This pic is not an agave of course, but shows a point in genetic variability. I had a couple large trays of small plastic cells where I was growing cactus seed from either Mesa or Alplains about twenty years ago. They were selected for cold hardiness from high elevation populations out west. Anyway, I transplanted the early ones and the trays got pushed to the side of the deck and forgotten for a couple decades. I found them yesterday when clearing a spot to put some potted agaves. Despite no care for twenty years sitting in the small plastic cells through rain, drought, heat, and temps to 35 below zero, a few are still alive. The most amazing thing is that the tray of cells (now rotten from UV exposure) was in a nonperforated tray that held water. I found these in standing water well above the soil line, and they no doubt endured that for weeks at a time. Most died but this guy survived and seemed to thrive.

In agaves we now have more selections from the truly alpine populations of Parryi between 6800 and 8200 feet where both summer rain and winter snow is on par with the western Midwest. Growing in pine woods as opposed to lower elevation desert conditions. Also some natural and man made hybrids could have some outliers displaying more resilience than expected. Maybe a select few from seeds from these populations can push the boundaries where we can grow them in the cold dry winter areas.

[jnewmark]

Wow, that's quite a story, although I think " hardy " cactus can take a lot more Winter conditions than other " hardy " succulents. I've had certain types of Echinocereus survive all kinds of cold, wet, freezing winters, some uncovered, while the " hardiest " Agave Utahensis did not last one Winter. Winter hardy Yuccas are the only other Winter hardy succulent that seems to be able to take any kind of Winter condition you throw at it here, along with all the hardy Sedum stonecrop plants.

[Meangreen94z]

Wow, that's quite a story, although I think " hardy " cactus can take a lot more Winter conditions than other " hardy " succulents. I've had certain types of Echinocereus survive all kinds of cold, wet, freezing winters, some uncovered, while the " hardiest " Agave Utahensis did not last one Winter. Winter hardy Yuccas are the only other Winter hardy succulent that seems to be able to take any kind of Winter condition you throw at it here, along with all the hardy Sedum stonecrop plants.

Hesperaloe parviflora is borderline on surviving there. Orostachy and Jovibarba are other succulent stonecrops that may survive in your climate. There are certain Manfreda rated to zone 5. You can do a combination of things and also bring the slower growing Agave in for the winter, and replant in Spring.

[westfork]

Hesperaloe parviflora is borderline on surviving there. Orostachy and Jovibarba are other succulent stonecrops that may survive in your climate. There are certain Manfreda rated to zone 5. You can do a combination of things and also bring the slower growing Agave in for the winter, and replant in Spring.

Thanks, we are doing a combination of lots of those. Over the years we have learned that provenance of the plants means a lot. Often there is only a tiny percentage of a particular species genetics that survive here, but they often thrive. We did acquire some manfreda virginica from three populations along its northern and northwestern range - Between central Missouri and Indiana. They will take some babying to get acclimated and don't seem to like our low humidity and constant sun - They may be more of a shade plant here. Lots of cactus and various western yuccas do well (we are in the native range of Yucca glauca). Orostachys spinosa have actually naturalized in northern Wisconsin. We are not having luck with them because various birds and mammals enjoy shelling out the small leaves. Winter testing a whole slew of sempervivums, concentrating on the jovibarba and calcariums.
Experimenting with a lot of agaves that do well in gardens along the front range in Colorado as our climate is just a few steps beyond theirs.
With most plants winter is our killer season. Not only from the cold, but most plants desiccate from the constant sun, rare precipitation, and very low humidity.

I am playing around with your idea of less hardy agaves that can be dug up for winter. I am making a list of plants that can take moderate cold (at least 10 f) and are moisture tolerant so can be put out early in the spring and left out until just before deep soil freeze in late fall. Perhaps some of the hybrids from PDN.

[Meangreen94z]

If you can find an Agave ‘Blue Bell Giant’ I can atleast verify they took a wet 3°F with minimal damage, most of it was the weight of thick initial ice buildup .

After 2/21

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This week- about 4 feet tip to tip

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This week

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[westfork]

Thanks for the suggestion. I ordered some of the PDN crosses involving ovatifolia, lophantha, and pseudosalmiana, pseudoferox (or whatever those americana, asperrima, & gentryi triple hybrids are currently called) - Twisted Tongue, Stairway to Heaven, and Emerald Giants. Looks like these should handle any moisture from spring to fall and have enough cold tolerance to take some chill before they are dug up for the winter. And who knows, maybe the genetic combination on one of the seedlings might show better than expected cold hardiness where some root and pup missed during the fall removal might actually survive some mild winter and surprise me the next year.

[Gafoto]

Sad to see this thread active again. Must mean fall is on the way. I wintered over a few things in pots last year since I was in between homes/locations. Lots of things went in the ground this spring so lots of plants to be tested. Everything went into beds with good drainage so I’m hoping that will be enough for the parryi, havardiana and parrasana.

My question is: if I cover plants like ovatifolia and ‘Silver Surfer’ which are right at my hardiness zone (7b) will they get used to winters or would I simply be delaying the inevitable if I leave them uncovered the following winter? They’re both in the 12-16” range so small but not tiny.

I for sure plan to cover the small utahensis and victoria-reginae I have planted for a couple of years. They’re small so a five gallon bucket on cold and snowy nights seems doable.

I ordered some of the PDN crosses involving ovatifolia, lophantha, and pseudosalmiana, pseudoferox (or whatever those americana, asperrima, & gentryi triple hybrids are currently called) - Twisted Tongue, Stairway to Heaven, and Emerald Giants.

I also paid the PDN tax for a few of those. There's a person on eBay selling these lopantha x salmiana 'Logan Calhoun' hybrids which look almost identical to the x loferox 'Gatorade' hybrid that PDN is selling. The eBay hybrid is exceptionally vigorous. Looking forward to finding it a spot in the garden next spring.

[westfork]

I also paid the PDN tax for a few of those. There's a person on eBay selling these lopantha x salmiana 'Logan Calhoun' hybrids which look almost identical to the x loferox 'Gatorade' hybrid that PDN is selling. The eBay hybrid is exceptionally vigorous. Looking forward to finding it a spot in the garden next spring.

That Ebay plant seems to be equivalent to a Stairway to Heaven. Gatorade's seed parent (Hacksaw) is a selected Stairway to Heaven clone, so I see why the strong resemblance. Gatorade's pollen parent (Grey Gator) would bring some other (but similar) genetics into the mix. Nice size.

[Meangreen94z]

Thanks for the suggestion. I ordered some of the PDN crosses involving ovatifolia, lophantha, and pseudosalmiana, pseudoferox (or whatever those americana, asperrima, & gentryi triple hybrids are currently called) - Twisted Tongue, Stairway to Heaven, and Emerald Giants. Looks like these should handle any moisture from spring to fall and have enough cold tolerance to take some chill before they are dug up for the winter. And who knows, maybe the genetic combination on one of the seedlings might show better than expected cold hardiness where some root and pup missed during the fall removal might actually survive some mild winter and surprise me the next year.

I ordered earlier this year and hadn’t seen they added on “Emerald Giant”. I received an offset from Mike Papay(MJP on here) a couple years ago. He helped create that hybrid with PDN, I guess they tested it out for a number of years before they had enough to offer for sale. Hopefully he starts posting on here again, his garden was an inspiration for those in wetter colder climates.

[jam]

My question is: if I cover plants like ovatifolia and ‘Silver Surfer’ which are right at my hardiness zone (7b) will they get used to winters or would I simply be delaying the inevitable if I leave them uncovered the following winter? They’re both in the 12-16” range so small but not tiny.

I want to believe it helps. I do help border-zone plants to get over the first maybe first two winters. I think this strategy works mainly with young plants. They don’t have the mass of adults and are still on a learning curve, thus able to acclimatize better than bigger plants.

@Meangreen94z Interesting. PD states it contains the genes of Agave americana, A. asperrima, and A. gentryi, which are not at the top of my cold tolerance list but wet 3F sounds really promising.

[Meangreen94z]

My question is: if I cover plants like ovatifolia and ‘Silver Surfer’ which are right at my hardiness zone (7b) will they get used to winters or would I simply be delaying the inevitable if I leave them uncovered the following winter? They’re both in the 12-16” range so small but not tiny.

I want to believe it helps. I do help border-zone plants to get over the first maybe first two winters. I think this strategy works mainly with young plants. They don’t have the mass of adults and are still on a learning curve, thus able to acclimatize better than bigger plants.

@Meangreen94z Interesting. PD states it contains the genes of Agave americana, A. asperrima, and A. gentryi, which are not at the top of my cold tolerance list but wet 3F sounds really promising.

Agave protoamericana is a natural hybrid of americana and asperrima. They burned but came back in the Austin area after single digits. Most of them flowered the following summer as a reaction to the damage. There is a variety of Agave asperrima that didn’t even burn from temperatures near 0°F in Central Texas. Some other forms had minor burn. Supposedly the variety from just south of Big Bend in Mexico is the hardiest. The other parent Agave ‘Bellville’ is an unknown, I doubt they did DNA testing to determine it’s origin.

[westfork]

I ordered earlier this year and hadn’t seen they added on “Emerald Giant”. I received an offset from Mike Papay(MJP on here) a couple years ago. He helped create that hybrid with PDN, I guess they tested it out for a number of years before they had enough to offer for sale. Hopefully he starts posting on here again, his garden was an inspiration for those in wetter colder climates.

I learned a lot from reading Mike's posts, and his reports of what survived the cold both at his garden and at PDN are very useful in selecting for hardiness. His work really helped advance the genetics for all of us.

[jam]

My question is: if I cover plants like ovatifolia and ‘Silver Surfer’ which are right at my hardiness zone (7b) will they get used to winters or would I simply be delaying the inevitable if I leave them uncovered the following winter? They’re both in the 12-16” range so small but not tiny.

I want to believe it helps. I do help border-zone plants to get over the first maybe first two winters. I think this strategy works mainly with young plants. They don’t have the mass of adults and are still on a learning curve, thus able to acclimatize better than bigger plants.

@Meangreen94z Interesting. PD states it contains the genes of Agave americana, A. asperrima, and A. gentryi, which are not at the top of my cold tolerance list but wet 3F sounds really promising.

Agave protoamericana is a natural hybrid of americana and asperrima. They burned but came back in the Austin area after single digits. Most of them flowered the following summer as a reaction to the damage. There is a variety of Agave asperrima that didn’t even burn from temperatures near 0°F in Central Texas. Some other forms had minor burn. Supposedly the variety from just south of Big Bend in Mexico is the hardiest. The other parent Agave ‘Bellville’ is an unknown, I doubt they did DNA testing to determine it’s origin.

With every post you bring up new candidates for my experiments. Protoamericana and asperrima. The list updated. I wish many of these were easier to come by. Not fair these beautiful plants evolved only on your side of the pond

[Gafoto]

Protoamericana and asperrima plants are rather uncommon. To be honest they aren’t the best looking “large” agave but apparently they’re hardier than most. Aridlands has seedlings of both available. Mine are small enough that I’ll probably be planting them in spring 2024 or 2025 for testing.