Have you check if the brown part is mushy, the roots too (rot alert, but hopefully it's not it..)? Too much water, perhaps? Stop watering and get it out of the potting soil to dry out for a while, just to be safe..

I think it's starting to rot due to overwatering as well.

These types of Haworthia have very firm, rigid leaves and do not require as much water as other species in the family. Because of this, it is also harder to see when the plant needs water.

If the leaves are soft and rotting, try to remove them without damaging the stem. As long as the stem and roots are not rotting yet you can save the plant, although it will still be visibly damaged.

I have a similar species and when grown inside under natural light, I water it every two to three weeks and still worry it might rot. It is in a very gritty (no soil) non-water-retentive mix.

I suggest you pls. remove it from that pot as it seems the saucer cannot be removed. If it can be then OK, but it looks ceramic & like it's attached.

I suspect that your mix which initially appears well draining is defeated by the fact that water can't drain out the bottom of this pot (nor be reabsorbed into the pot as it's been glazed). Also looks like bark & maybe even peat in that mix; (neither good for this plant) what mix is that pls?

When you touch the upper part, does the whole thing wobble or seem lose in the pot?

I think this is Haworthia reinwardtii (sp?), on of the columnar Haws, & it's rotting from the bottom up. If it were mine, I'd remove from the pot, cut off the rot, sprinkle w/ cinnamon & then leave out of mix for several days before repotting DRY. I wouldn't water for at least a week after that.

Lena

It's most likely rotting from the stem from being too moist in a low light situation (office). The soil also looks quite damp at the surface despite the rock dressing. You could pull it out of the pot, rinse off the soil, and cut away any rotten tissue until you find healthy green tissue, let the cuts callous for a week, apply rooting hormone, and try to reroot it by setting the new base just beneath the soil. Withhold watering and only mist lightly every other day for about a month in bright natural light (or strong artificial light). In that size of pot for that plant, you would need very well drained soil and to water (thoroughly) only occasionally (every 2 weeks in partial sun conditions). It's a cute haworthia, one I've been keeping an eye out for. Good luck with her.

I completely understand the desire for plants in an office. As for good office plants, pothos and zamioculca are pretty solid choices. Cacti and succulents rarely ever survive that condition.

I would agree with those who have said the bottom is rotted. IMHO, the ONLY salvation is to do a major surgical procedure ASAP. You must behead this back to clean green viable stem, allow to callous for a week and replant in very gritty mix. Keep warm and ONLY light misting until roots grow from the base.

If it's too late for the above, you can always remove viable leaves and attempt to root them.