Succulents are the best choice for a beginner’s indoor garden, but you have to keep in mind that they are not so foolish. Even if succulents are on the hard-to-kill houseplant list, you have to know that they are still plants and neglected completely, will wither and die.
Succulents, as well as cactuses, respond to many environmental stressors by stopping growing and dropping leaves, reducing their energy needs. Heat, frost, low or high light, improper watering and chemical shock can all cause leaf drop, often quite suddenly.
Temperature could be the main cause of leaf drop
Yes, most succulents are adapted to hot and arid areas, but somehow they respond by dropping leaves when they are stressed by heat or drought. If your succulents look wilted or sunburned, I advise you to move them to a shady place.
Of course, succulents may respond with leaf drop if they face freeze. Cold and freeze can blacken and burn their leaves which will eventually fall off.
then the Light they receive
Since succulents are adapted to areas with lots of sunlight, you should provide them the perfect environment. They grow beautiful in well-lit areas, and when they are lacking of light will turn green or yellow which will cause leaf drop and plant’s death afterwards. If your succulents show signs of any of these problems, I advise you to correct the problem.
Another matter can be Fungal Infection
I your succulents are suffering from some sort of fungal infection, you may act immediately in order to get rid of the pests. However, I advise to act carefully, because chemicals can also harm the plant and not only the fungal disease. Read the package directions and don’t reapply more than it’s written on the label.
Succulents are well-known for their less water requirements. Overwatering will swell their leaves and if they don’t get a chance to dry out, it will cause leaf drop. Before watering, make sure that the soil is completely dry and the leaves look a little limp. Use pots with drainage holes for succulents.