Question for those who grow sinningias -- I have a small sinningia leucotricha plant, and recently the tips of the leaves started progressively drying up. Normally I wouldn't worry about a few dry tips on plants and just wait an see what happens, but considering that this year this plant will only have the four leaves it's got now, this kind of sucks, I don't want it to lose 2 or 3 of its 4 leaves :-/

So the question -- what is it that the plant might not be liking? I leached the soil just n case it's fertilizer burn, and I'll cut down on fertilizer till it stabilizes (it was getting the same concentration as AVs and chiritas). Anything else I should try? The plant is in the south window, and the humidity here is about 50-60%, temperature 62-70F. I actually have two leucotrichas in the same windowsill, and only one has leaves drying up, the other one is perfectly fine.

Thanks in advance for any ideas!