Sigh. To begin with, we've had a ton of rain in the last couple of weeks & I'm hoping what my plants are suffering from is a result of the rain & not something more sinister! Please take a look at the pic(s) below & 'hopefully' relieve my fears. What are the white spots? The spots are all over the plant. However, four nearby plants do not have them.
Thanking you in advance for your help, Sally

Hi SallyAnnette16 to NGA
We have a forum for Sempervivum that has some knowledgeable folks. I have alerted them to your post and I will also give you the link to that forum.

http://garden.org/forums/view/...

@goldfinch4 @valleylyn I hope you can help a new member with unhappy chooks

Hi SallyAnnette16, glad to have you here on NGA!

Thanks for the call-out @Moonhowl.

It looks like slug or snail damage to me. In the bottom picture, do you have mulch around your plant? Since these are alpine plants they grow best in rocky soil with very good drainage. Mulch will keep them too wet and will a provide an ideal environment for slugs and snails to hide in. I'd remove the mulch. But other than the damage, your plants look very healthy.

Would love to have you join us in the Semp forum!

@SallyAnnette16 -- looks to me like a mildew/mold problem. I would pull them up and pull off the infected leaves. Just pull them up, let the roots get exposed to the air also. If the mildew is not too bad, you might be able to just wash it off, but removing the leaves would be better. Let them dry out in a well ventilated place inside your house or garage or other dry area for several days. Then replant them in an area with good drainage. They are pretty hardy plants, so I think you have a good chance of reviving them.

Thank you Goldfinch4!
Most of my plants are tucked in rocks on a slope. But, I did put a few up on a ledge with some grasses & that area is mulched. (Interestingly, my neighbor's lawn had grubs this year.) It's been so wet, the ground hasn't been able to drain fast enough. I actually think I can grow Cannas at the bottom of the slope. I'll take a good look today (pull up some of the rocks) & see if I can find the snails/slugs. I can't thank you enough, I was afraid it was some strange fungus & I was going to have to pull them all out.

hmmmm, yes, might be slug damage also. Good guess goldfinch4.

To Cwhitt,
This is the news I was hoping I wouldn't hear. There are hundreds & hundreds of plants & leaves. Sigh. I'll be busy today.

To Cwhitt & Goldfinch4,
I want to thank you both for your help, you have given me something to go on. I moved into this house in 2014 & the yard had been severely neglected. I planted like crazy last year. This is my first experience with Sempervivum & they've exploded in size & with chicks. I've gotten kind of attached to 'em. 😆

Yes, they are addicting little plants! Look forward to talking to you more over in the semp forum!