Agaveville

Fantastic info and a perspective that is clearly informed by decades of experience. I picked up tips about wind--hadn't considered that as a separate variable. Thanks for sharing this with the community.

I have his book 'Cacti and Succulents for Cold Climates' which is very good. From a UK perspective it is hard to draw parallels as our climates are so different. Here, for example, a windy location is generally better as it takes stagnant humid air away from the plant and helps to wick moisture out of the soil. But this sort of stuff always makes fascinating reading.

Very interesting....
I have experimented with 4 types of Agave here in the North of England.
All 4 are planted in the same raised bed and have been in the same location for three summers and two winters, I have a cover of polycarb I place over the bed around the end of October that is open at the front and both sides
So far;
Agave Montana no winter damage
Agave Parryi no winter damage
Agave Americana medio picta alba no winter damage
Agave Americana variegated suffers every winter, which I found surprising as I had assumed this was hardier than the medio picta alba
However the winters have not been particularly hard for the last few years........

AgaveMad...thank you for sharing your observations. I'm in Philadelpia, PA, so very interested in your experiences with winter hardiness. Are your agaves potted? I will be trying a few outside this winter, also covered to stay dry. Mine are potted in clay. Will maybe try baccarat (a Montana x gentry hybrid, I believe) parryi truncata, leopoldii, zebra...maybe a few others.

Paul, I think he may be talking about winds increasing chances of cold damage to leaves.

Not sure why winds would exacerbate cold damage. Desiccation, maybe, but cold air doesn't get any colder if moves quicker.

Here in the perhaps balmier southeast of England I am growing the following taxa in no particular order other than how they pop into my brain - a couple, such as albopilosa, are newly planted this year, some have been with me for 25 years and veterans of some nasty winters.

montana - gotta love this species - about half a dozen plants!
gentryi – another favourite of mine, I have several clones planted
ovatifolia
salmiana - a couple of clones
salmiana ssp crassispina – another favourite - several clones
lophantha
victoriae-reginae
x viridis
striata
stricta
dasylirioides
albopilosa
parryi
schidigera
filifera
heteracantha
wocomahi
mitis
montana x mitis
bracteosa
obscura
parrasana
atrovirens
x 'Mateo'
polianthiflora
couple of sp. Unknown from Mexico.

If I lived further north I would be trying Agave bracteosa, filifera and striata outside as they are amongst the toughest. Perhaps ovatifolia, too.

Wow--what a list! What's the coldest you tend to get?

I've lived here for 23 years and the lowest temperature in that time was -8C in January 2010, which looks like it is around 18F. But it wasn't so much the absolute low temperature that caused a problem, it was the fact that the temperature didn't get above freezing for over a week and we had around 2ft of snow. English snow is wet, horrible slushy stuff, not nice dry, powdery insulating stuff.

Of those listed, the following were planted before the bad winter and survived:
montana
gentryi
salmiana
salmiana ssp crassispina
lophantha (I guess that should be univittata now)
striata
stricta (unbelievably)
parryi
schidigera
filifera
heteracantha
bracteosa

This gives me great hope, as 18F is a typical lowest point here in the winter, but not common. I am also optimistic seeing that 2 I want to winter outside are hybrids of those you listed (baccarat, Montana x gentry and leopoldii, schidigera x filifera). I have a quadricolor (univata?) that I will try as well.

The trick will be, I think, strategic placement of garden umbrellas to provide dry yet sunny conditions. I'll need to be on top of it so I can open them on days/nights calling for rain or snow and then taken them down after.

I really do appreciate this perspective. Do you know of any other sites where succulent growing is addressed for cold climates?

Paul, could you list Aloes as well?

Thanks.

That is easy, Mick, as the lists are much shorter.

The only survivors of winter '09/10 were striatula, aristata and 'Cosmo' - which I think is a x Gasteraloe despite what the labels says.

I now have those 3 plus
polyphylla
spectabilis (possibly this is just a form of marlothii?)
A couple of un-named hybrids
various different clones from the 'Perfoliata group'
maculata
'Hercules'
mutabilis

I've grown and lost loads including brevifolia, some of the grass aloes such as humilis, variegata, ecklonis, verecunda and cooperi, arborescens, x salm-dyckiana, ciliaris, grandidentata, greatheadii, pratensis, broomii, reitzii. Some of these I would try again, space permitting.

Edit - one I have unfinished business with is haemanthifolia. For some reason it is very rarely encountered in the trade here and the two offsets I did manage to get hold of came by a trade. This is reputed to be both cold and wet tolerant (and very hard to grow - maybe there is my answer right there).

I know Aloe haemanthifolia grows in the Western Cape of S Africa, often a little uphill from A. plicatilis, thus the cold tolerance. From everything I read it seems difficult, and also might require a burn ecology. I think it wants winter rain and no summer rain.

I've had and lost haemanthifolia which I got from STC. Seems to need cool damp conditions not unlike polyphylla and I only lost it due to a severe red spider mite infection in the heart of the plant. Not been able to find a replacement yet.

Paul, as you know I managed to keep a large ferox outside for a couple of winters until a really hard winter did for it.

The large polyphylla stays outside all year round and has for some years now.

Yes, it was your success with your ferox that prompted me to try the spectabilis. I put an umbrella over it at the moment as it is still quite small but it has been ok for two mild winters with that little extra help in winter. I have lost count of the number of polyphylla I have lost - keep on trying! Two at the moment have been out for 3 winters. But I know of folks who have grown them to flowering size and beyond outdoors in gardens that, on paper, are less benign than mine.

Seems haemanthifolia is elusive everywhere!

I guess you plant your polyphyllas direct in the ground?

Yes. Freely draining, mainly mineral soil and on a slight tilt. I've read that they favour an organic soil, though - peaty with bark chips for drainage - what do you grow yours in?

Potted in my standard cactus soil but with 50% orchid compost added. Needs a repot which I'm putting off as it will be painful!

This has been outside for about the last 10 years. No idea what it is (there may be a label lurking somewhere) and desperate for a repot and clean up.

I don't know if this helps but there is internet article someplace about a great looking cactus garden in eastern and very dry Oregon or Washington- maybe Washington? All could take like 0F temps.

Gee.S wrote: ↑Sat Sep 09, 2017 3:29 pmCold.pdf

Adding Agave polianthiflora to my list...

@Paul S , any more insight on hardiness of those new aloes you mentioned addin in your comment here?

Long term here there are no more to add to striatula and aristata. Others never make it through my coldest winters but are OK through milder ones. The winter before last was bad throughout most of the UK. Not because of how cold it cold but because the cold arrived very suddenly on the heels of a long, mild and exceedingly wet autumn when everything was still actively growing. That killed off most of my more experimental plantings except for those in the most protected microclimates.

K, thanks. I will try to eventually find some of the others, but first want to start with the most hardy. I got an aristata for Christmas after reading about their cold hardiness at pdn. Once I am shopping for plants again I will look for striatula. Then later on when I have more space consider the others. Probably won't be pushing their extreme limits for a while - keep in a hoop tunnel or some other cover on cold nights/storms. Maybe once things reproduce enough and I have some I am willing to experiment on. But as long as they can handle a semi-sheltered life here I will be glad.

Good info on season changes and types that they struggle with. Thanks. Mild and wet autumn and then super cold blasts sounds like a lot of winters here (not this year, though). Something I will have to remember.

The jury is still out on that Aloe aristata. I bought a supposed 9000’ specimen from Ethical Desert and it definitely melted last winter under heavy snows and single digits temps. Another one is in the ground this winter to see how it does and I pulled another pup inside for a third and final try if it doesn’t stick. My guess is that it’s Pueblo hardy which means it can handle cold if it is bone dry but not snow.

The other aloes he claims are cold hardy are….mixed. The Aloe tomentosa was taking frost damage in the 20s and is probably mush now. The Gonialoe variegata he sells was good into the 20s but is currently buried so we won’t know for a bit. Probably won’t bother with those again. If they’re hardy they would probably require full covers and I just don’t love Aloe enough for that.