I wouldn't fertilize now either. I agree rooting in spring has its benefits, but since you're trying to save the leaf at this time, you can't hold off till spring.. Like Rjm stated, diving the leaf is one way to root. Actually, I've seen pics of how rooting Sans is done..One leaf is cut into 2-3" pieces, set upright/angle in well-draining soil. The problem is, since your leaf is yellow, which normally happens when Sans are over or underwatered, this leaf may not root..When rooting, heatlhy foliage is recommeded..Neither the oldest nor youngest leaves are advised. I'm not saying your leaf is unhealthy, since it's still firm (no rot, right?) So, it might have a chance of survival with some work. It's also a good experiment. I wouldn't use the entire leaf to root. You've a better chance at success cutting into pieces. If you decide to go this route, there's no need for plastic (humidity) In fact, you want the soil to dry out to a degree, adding plstic will keep soil too wet. The best container is a small, shallow dish/tray. Set cuttings a few inches apart. Place tray in medium light (no direct sun) If you use Superthrive Hormone and Vitamins, add a small amount once a month..If you don't have/use Superthrive, perhaps a light dose of Fish Emulsion will help..a very light dose. Good luck, Toni

If the plant is grown on a slant the water will fall out from the leaves, these usually grow on hillsides, and their heads will face the sun. The more water you give it this time of the year the more bottom leaves it will lose, the fan is not helping it at all, they do need circulation in an inclosed room, but not directly on them. Check the soil, if it came directly from where you bought the plant change the soil, the plant may not even have roots. These grow in the spring, and like it on the cool side growing on cliff sides or hills of rocks, in Mexico mostly. I also live in So. Calif. Los Angeles Area, we grow ours in the greenhouse and it gets morning sun, and sun from a glass roof top that is high. My training is from the Huntington Gardens for the past l8 years, this plant may be started by cutting off the top and leave 2" of stem, them putting it into an empty pot until it gets roots, then replanting it into a very gritty mix, with very little potting soil . Follow the directions given just above. I have kept my own out all winter long and it did just fine. I check my soil, by putting a chop stick in the soil or a pencil, leave it in 5 minutes. Remember the root ball must get the water that is where the roots grow, not just the sides of the pot. You have a very small plant at this time. So give some time to grow. Best of luck, Norma

It kind of looks like an Echeveria pulidonis.

The first suspect would be the contrast in light levels between where it was sited outdoors and what new light levels are indoors. A plant's ability to adjust to changes in light levels is not unlimited. Something I wrote about a plant's ability to adjust to changes in photo loads: Light Acclimatization The degree to which a leaf can 'acclimate' to changes in photo load is limited. IOW, you can't expect a leaf that emerged under a full sun light load to acclimate to light levels in a dim corner, any more than you can expect a leaf that emerged in a dim corner to acclimate to a full sun site; this, no matter how long you allow for gradual acclimation. Too, the plant's ability to adapt to higher light loads is greater than its ability to adapt to lesser light loads. Using a 1-10 numerical example to illustrate (numerical value of 1 is low light, 10 is high light): If a leaf emerges where the light level is measured at 5 units, it's range of adjustment might only be to 3.5 on the low side, but 8 to 8.5 on the high side. When the level of adjustment required is greater than what the plant is genetically programmed to deal with, the leaf is shed, and this can occur with conspicuous or relatively inconspicuous damage to the leaf. While shed leaves can never be replaced, per se, new branches can form (with new leaves along the new branches) in the axils of dying leaves or from latent buds immediately above scars left by shed leaves. Too, whenever a new leaf appears it will be perfectly acclimated to whatever the photo load is where the plant is positioned (within the limits of what it is genetically programmed to tolerate). The regulating mechanism that determines whether leaves are able to adapt or destined to be shed centers on the flow of a growth regulator, auxin, across what is called the abscission done, located at the base of the leaf petiole (stem) where the leaf is attached to a branch. Steep declines in the rate of auxin flow causes an abscission layer to form, which effectively forms a wall between the dead/ dying leaf and viable plant parts, soon after which the leaf separates from the rest of the plant. Al