Damge to leaves reducing hardiness

[ChrisG]

I posted last year that i noticed with a lot of my succulents that where leaves were marked or badly damaged in winter this seemed to start at points were the leaves were not in perfect condition before the cold snap. For instance a leaf that has been torn or spikied by something, or been eaten by slugs were the first to mark. I have been keeping a very close eye on my succulents this year and I have noticed exactly the same. The only damage so far is to leaves that have some physical damage to them.

The problem then seems to be that once one leaf is damages it spreads and the rest of the plant can be damaged by cold. I have two examples of this in the dry bed, an echeveria where two leaves had previously been munched upon by slugs started to rot int he cold and now the whole growing point of the plant has gone, and an aloe where one of the older leaves had been torn where rot is starting to appear on the other leaves around it.

Have others noticed this with their plants? I am no considering removing damaged plants to give them extra protection and to try and stop further damage.

[Vic]

Chris its funny you should mention this. I had the same happen last winter (before now) when i had the odd bit of brown spotting on a small a.neomexicana planted out, the brown spotting then spread to other agaves close by which i am convinced was not cold damage as last winter was the mildest i have ever recorded down to -4.5c last december. All affected agaves still had a rainshelter for protection.

In the spring i was bit brutal with them and cut out all damaged leaves as i decided it was fungus of some kind? The good news is that it worked and the fungus or whatever it was has not returned.

Incidentally the only agaves that were not affected were salminana ferox an my variegated americana.

[Cathy]

I noticed horrid brown spots on the leaves of my fairly largeish Agave Americanas (plain and variegated) which appeared after we had heavy hailstones before I had the rainshelter put up.
I have wondered if I should cut off the damaged leaves as they are so unsightly but decided to let them stay until the springtime tidy up. A large A. Ferox seems to be unscathed

I must say that I have thought in previous years, that once damaged, the plants seem to continue to worsen until trimmed in spring when they perk up with the better weather.
This winter, I will l watch them more closely.

(I have put my small potted Agaves in a plastic growhouse which has overhead cover, have not checked them for a while. )
Cathy.