Agave Blue Glow - frost hardiness

[juper]

Hi-

Has anybody experienced the hardiness of this agave firsthand? thx

[rpw]

Last month we had a cold front with over a week of below freezing nights, with several nights below freezing for over eight hours, and two nights below 20 F.
One night I recorded 19 F for at least several hours, and the next night I recorded 17 F for several hours or more. Two young 'Blue Glow' plants (about 7-8 inch diameter) planted in an outdoor bed away from the house were undamaged.

Also of interest, unprotected Aloe pratensis came through unscathed, while Aloe brevifolia was completely killed...
And some Dyckias died but some survived...

Peyton

[juper]

Wow!
It's great to hear that they can withstand those low temps - even better that A. Brevifolias! (I'll keep an eye out for Aloe pratensis)

Thanks Peyton for sharing your firsthand experience. Zac

[CaliFlowers]

We're about 10 miles north of you, a bit more inland, and only a few (yet vital) degrees colder than Berkeley.

With a few very tender exceptions, the deciding factor for Agave adaptation in this mediterranean climate has more to do with moisture & shade tolerance. In my garden, species & varieties such as 'Kichijokan' , A. utahensis, A. arizonica, A. cerulata, A. deserti, & A. zebra sustain damage ranging from cosmetic to life-threatening, unless I protect them from rain. In a bright, wide-open southern exposure, some of them will tolerate the rain, but a few weeks of drizzly, rainy, overcast skies will usually cause problems, problems you won't see in the "New World Desert" or "African Hill" sections of the UC Botanical Garden, for instance.

Having said all of that, my two 1-gallon 'Blue Glow' are completely undamaged after two winters that took a toll on many of my other subtropicals. Unprotected.

Dry Garden in Berkeley has a fine specimen of "Blue Glow" bedded out that is probably 15 years old, and it gets a fair amount of winter shade.

Ken

[juper]

Thanks Ken for sharing your experience.

I will be adding few Agaves in my Western exposure front garden (Mediopicta Alba, Blue Glow, victoria regina, Parryii truncatas); everything will be on raised mounds (at the bottom of a slight slope) with adequate drainage hoping they all would withstand some water runoffs during heavy winter rains. On second thought, maybe I should rethink their locations... thx zac

[agavegreg]

Those that you list would be some of the ones least able to tolerate substantial winter rain runoff. I wouldn't put any agaves in a spot that will be under standing water in the winter.

[Steve Steward]

odd that i've seen blue glow consistently take damage under 25f here in Tucson.

[juper]

Thanks Steve,
Two different observations regarding 'Blue Glow'.

Peyton,
By any chance, is yours an Agave 'Blue Flame' instead? Because they tend to be much hardier.

[rpw]

Mine are 'Blue Glow', and I have five of them planted in outdoor beds. The two I reported on are on the north side of the house in an exposed location where many other C&S plants froze solid and died...
I took a few photos recently, but I don't have them with me at the moment, so I'll post them later when I get a chance.
Also killed by this same freeze were most of the numerous Queen Palms in town which die around 18-20 F, though we won't know until summer if any are still alive.
Lots of sago palms had their fronds badly burnt as well...

I'm surprised that 'Blue Flame' would be hardier as it retains so much of the attenuata look, and the other parent (shawii) is not very cold hardy, while 'Blue Glow' has a more cold tolerant parent in ocahui....
Agave ocahui not only takes all the cold here but also tolerates our wet winters and heavy clay soils with no problems, at least the one plant that I have had outdoors in the ground for some years now.

Peyton

[juper]

Thanks Peyton for the response. Blue Glows are pretty hardy - that's great news!

[Allen Repashy]

I am a bit surprised about the Agave'Blue Flame' observations as well, but one thing that could make it a good winter survivor, especially when it comes to wet, is that A shawii is a winter grower and by nature, designed to love our winter/spring rains. It does also have pretty good frost tolerance as a species. The one thing A. shawii doesn't like is summer watering. If you don't treat it like a winter growing bulb, there is a good chance you will rot it in the summer if watered regularly.

Allen

[Kevin Coniff]

Allen,

You should be on the alert for weevils with shawii when grown inland.

I had problems seveal years ago wit weevils on shawii, sebastianiana and truncata at my place outside of Jamul.

I wonder if anyone has had problems with weevils on 'Blue Glow' or 'Blue Flame'.

It would be nice to have a list of weevil host agaves, better yet a list of those that are not hosts.

Kevin

[thistlesifter]

Kevin,
I have had the borer from weevils in Blue Glow and Blue Flame. The pest killed one double headed prize 3 year old BG. I had just missed it entirely. We had borer in another potted BG and I was able to exterminate them there and in another bedded BF.

Since then I've watched all agaves carefully. I've grown Agaves here in Bonsall for 26 years. and had not been infested with them prior to the invasion in the 3 plants starting about 2 years ago. I've grown many dozens of agave taxa in the 25 years here including an old Attenuata X shawii hybrid that Paul Hutchison sold over 30 years ago at Tropic World. That shawii hybrid has never had the borer.

BTW, I did have a borinsect in an eight-foot Tricho I got at Dave Grigsby's haul away sale in 1987 (I think it was). Dave showed me how to get rid of it. I don't know if that borer was the same as the Agave beetle's larvae (borer).

Nasty looking little grubs and they are very tough like tough rubber. They look just like the ones that somehow end up in cheap tequilla or mescal bottles..HE HE HE!

They are anything but funny when you find them in a pile under a coreless/rootless Prize BG Agave! They pool under the rotting plant carcass and metamorphize into flying insects, probably small moths..

Bob Weeks

[rpw]

Here are the two 'Blue Glow' that survived last month's deep freeze. They are slightly larger than I guestimated earlier, about 8-10 inches across.
Peyton

[Tony Avent]

All:

Our winter of 2008/2009 took out Agave 'Blue Glow' in two locations at 9 degrees F., while the similar A. 'Burnt Burgundy' barely survived. Based on our trials, I'd say that both are good in Zone 8b, and marginal below that.

[agavegreg]

Peyton,

How wide are the leaves on your 'Blue Glow'? They look much wider than the plants I've grown, but it's hard to tell.

Greg

[agavegreg]

Tony,

Thanks for the info on those two cultivars.

Can you grow A. vic.-reg. and A. palmeri outdoors there?

Greg

[Tony Avent]

Greg:

There is a huge difference in hardiness of clones of A. victoriae-reginae. My oldest garden plants are near 20 years old and have seen no damage at 6F. I've lost other clones at 15F planted nearby...same conditions. The Agave 'Porcupine' clone from Yucca Do has shown excellent hardiness.

The same is true for Agave palmeri. I killed some clones from the Globe AZ area, while a plant from Sonora, Mexico is fine...go figure.