Aaron will be the one to chime in here...but I bet he'll say Dasylirion wheelerii.

Barb

Aaron will be the one to chime in here...but I bet he'll say Dasylirion wheelerii.

Barb

I agree, D. wheelerii is known for surviving low temps. Also try Dasylirion texanum and Nolina texana.

I have yet to find a dasylirion or a nolina that will survive a winter in my garden, but I bet they would with a cover. I'm going to try again, but this time my dasylirion will be covered. 😉

And what about Nolina microcarpa? [Some internet sources give it zone 6a]

My answer is no Dasylirion nor any Nolina will survive in 6a. But I have seedlings of Dasylirion texanum, longissima and wheeleri off to a good start on my heat mats. The test for 7a will be next winter.
Biggest factor is wet/cold freeze-thaw cycles. One or two thaws is alright for these on the edge of their limit. When you get more, or even dozens of thaws in a winter, your desert plant will be mush.
On the other hand, if in a long freeze it can't be below a maximum cold temp for the plant, or it goes to mush.
So hopefully almost daily your ground warms up mostly, to avoid frozen solid roots, which are likely less hardy than the plant itself... So 6a, I suggest protection measures.

And what about Nolina microcarpa? [Some internet sources give it zone 6a]

There is only one way of knowing, plant one and try it? I have tried one here but without luck, but I have seen them 20 miles south of here in a warmer zone 6, but I don't know if they are still alive. 😕

The only zone 6 hardy nolina I have seen so far is Nolina texana, but only lasted one season for me. It might be hardy if I kept trying. Also it looks more or less like a mound of grass. 🙂

PS. I have yet to try Dasylirion texanum. I have herd good things about it. 😐

What species is more hardy: Nolina microcarpa or Nolina texana?
[In my opinion N. microcarpa will be more hardy. Here is the map, where you can see the distribution of the different nolina species: http://www.bonap.org/BONAPmaps2010/Nolina.html According to these maps nolina microcarpa has much bigger part of its range in zones 6b and 6a, then nolina texana. http://www.plantmaps.com/usda_hardiness_zone_map.php]

I always thought Nolina texana was also found in SE AZ.
http://www.wildflower.org/plants/result.php?id_plant=NOTE

Nolina microcarpa can be very hardy, but depends where the seed came from. Just like any plant. I have seen some high in the nountains that would be good for hardy gardens. But most plants are raised for the better garden looks. Long tuffs on the end of the leaves.

Both would be worth a try, but texana lasted longer in my garden. I think a couple of years or so, maybe longer. I dont think microcarpa lasted through a winter. 🙂

Where I can buy nolina microcarpa seeds from the high mountains or from the northern part of its range? 🙂

Where I can buy nolina microcarpa seeds from the high mountains or from the northern part of its range? 🙂

That I dont know? I wish I would have brought some home when I found them, but I was following someone and could not stop my car to get them. 😡

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