Narcissus canaliculatus

[John85]

How hardy are they without snowcover but in good draining mixture?
This year the foliage has been badly damaged by a frost of -8¨c and they didn't recover.

[Maggi Young]

To be honest John, I'm not too sure how hardy they are.... because every time I have planted them here they have barely flowered the first year, then made a few leaves with a very occasional flower in the next year or two then disappeared altogether... maybe with a few leaves hanging on for a while.... so I'm not sure if it is frost that kills them off or they just dwindle away for some other reason. 

[Lori S.]

As this is one of the very few species Narcissus that is commonly available here as bulbs, I've planted packets of bulbs a few times and never had one survive the winter... although I doubt that's surprising in the least to all of you folks in zones 7 and 8.  
So-called "rock garden narcissus" (i.e. dwarf hybrids, usually) generally do well here, though, despite our normally inconsistent snow cover and low winter temperatures, so from that I have assumed that N. canaliculatus is less hardy.  (God only knows why it's sold here!)

[Paddy Tobin]

They grow very well here but can be shy to flower. I have one area where they flower well and another where I have lush foliage but only a very, very few flowers. Last winter we had -10C, exceptional for us, and they were all fine. This cold snap came in mid-winter when they were dormant and had no effect on them.

Paddy

[wooden shoe]

Half of them survived -17 C when they were in full dormancy. But last winter started mild but had a cold spell till -15.5 C and I can't find a trace of them. So I'm afraid they are not the most hardy Narcissus.