Hi Folks, I have a problem I think many of you are familiar with. rot I would like to begin this discusion by saying that I have already done extensive research on this topic, I customize my soil for good drainage and try not to over-water.
So far my rot prevention has been exceptional, but an unfortunate set of circumstances have put two of my favorite cultivars in jeopardy: This year I've expanded my collection to the point that my semp territory has spilled into full sun, during an exceptionally hot day that I was tied up at work some of my cultivars were damaged by the heat. In a desperate attempt to save them I moved my potted collection into a shady spot of the yard where the grass seemed never to dry. For all intensive purposes my plan worked, all of my plants recovered. Unfortunately I moved not just the cooked cultivars, but the entire collection. A week later Starshine and Glauca Minor, two plants that had done alright in the sun began to rot in the new darker and wetter microclimate. I repotted them in fresh soil without watering, then gradualy moved them into the sun, I plucked all of the dead and rotting leaves and rinsed the potentially tainted soil off the roots, but the rot continued. I then tried to dry out a plant in my attic by the window without soil, sheltering the roots from light only with cardboard. It's been three days and the drying rosette is still in decline. I saved the chicks from both plants of which I only had a single mature specimen, so the cultivars are safe, but I hate to just sit and watch my primary rosettes rot into nothing. If anyone has a treatment that I haven't tried, something that isn't just a purely preventative measure for rot control, I think we could all use to hear about it. Thanks

Hi GeologicalForms
Can you give us some information about your growing conditions. Such as growing zone, what part of the country you live in? This information can make a difference. Also humidity.

Photos are also very helpful.

Hi Lynn,
I live in Portland Oregon, zone 8b I believe. I'll try to get some pics up soon, but it's the classic rot scenario; outer leaves becoming translucent and dying at an unsustainable rate, an unpleasant smell, overall discoloration of the rosettes. Likely to be the same problem you'd get from over-watering. The rosettes are now about a third of their original size. I had put them in a shady part of the yard where moisture seemed to be retained by the grass, the soil they were potted in seemed to dry much slower than their usual south facing full sun location. I assume they just didn't dry up fast enough, but since I've tried to dry them out the rot's not letting up. Is there anything that can be done?

Clean every speck or rot off, lay on a clean paper towel in bright light but no sun. Indoors where it is cooler. Just let them dry out on the paper towel. Hopefully the will callus over if all the rot is removed.
Please keep us updated.
It is always stressful for us when something like this happens.

@tcstoehr Tim, did you recently have some rot problems.

Thanks Lynn, I'll try implementing the paper towel and take them away from the window. I have also considered using soap or charcoal to wash them with, and possibly resting them bare root by a fan, let me know if you think that could help or if it's too drastic.

By all means leave them bare root for at least a few days. And watch for any more rot, and remove immediately.
Our humidity is pretty low @ 60%. Do you have air conditioning in your home? The fan might be a good idea as far as air circulation. But no sun.

I do have an AC unit but I use it as little as possible. I'll put the fan on them tonight.

The fan should work just fine, especially if the plants are by an open window tonight with the cool evening air flowing across them.

As promised here are some pictures
of glauca minor, before and after the pruning session last night. The leaves I removed had gone translucent over the course of just two days, and it was already drying bare root by the window for that period. This is it's fifth day out of the ground. At this point the rosette is less than a quarter of it's pre-rot size. If the fan and the paper towel don't make a difference fast it's fertilizer.

I would also clean out all that old soil debris, I see what looks like bark particles? You can gently rinse the roots to clear out any remnants of the old soil. When you repot don't use a cactus mix, use sandy loam if you can get it and mix in chicken grit, then top dress with chicken grit. I wouldn't fertilize a plant that is in distress. Water and leave to dry out outdoors in a bright area, but no direct sun.

We'll Lynn, I want to thank you for trying to help save Glauca Minor, but I have to say the hand of the reaper is awfully close now, the day in front of the fan on a paper towel didn't stop me from having to prune off half of the remaining foliage today. The roots do appear similar to bark chips but I washed the dirt off pretty good and can't find any remaining soil on the plant, perhaps soap would have helped. The lack of response by others to this thread may be proof that once the rot takes hold there's no coming back I have to ask, have you ever saved a semp that had already begun decline due to rot? I've gotten as far as to revive plants that had begun to show discoloration by re-potting, repositioning or restricting water, but I couldn't honestly say that once a plant had lost a substantial amount of foliage I have ever been able to bring such a plant back from the brink.

I have saved semps that had a major amount of rot. First I remove all leaf material that appeared to be abnormal. Then check the crown for any signs of being soft, if soft I cut all crown material away until it was down to healthy tissue. Let callus over and replanted in a fast draining mix with chicken grit top dressing.
Treemailing you Sol.

Sol to your point, I didn't respond to you because I haven't had good luck saving plants that are already rotten...At this point since I have many others I stopped even trying to save them, I do however have very good luck saving the offsets (if any) by just removing and planting them elsewhere. Also I have had the experience of having semps in full sun rot without water being the problem...If I see the semp is looking funny and I catch it early enough then I've had luck by doing what you did

I'm usually not concerned about a rotting rosette if there are offsets to replace it. I do make sure I remove the offsets connected to the mother rosette and replant them later as I dispose of the rotter. Sometimes there is no replacement and I do try to remove the affected leaves and then I take the time to place small rocks under the rest of the leaves so that they don't sit on wet soil. When the rot gets into the main stem, I am not as heroic as Lynn. I don't do surgery. I document the loss as a "used to have" in my plant list and then when the time comes to buy more semps, that "used to have" list contains the names of must-get-again semps to buy.