Snake plant thrives best when neglected. It doesn't require fertilizer and can be left in any kind of light. One of the main reasons a snake plant will wilt is overwatering. As a desert plant it is prone to root rot. Symptoms of root rot include wilting, brown or discolored spots on leaves or leaf margins and mushy, brown roots.
Fungi in the soil cause root rot. Wet conditions cause these fungi to spread and enter damaged or water-soaked roots. If your snake plant starts wilting and you watered it recently, gently pull it out of the pot and check the roots. If you see a few, brown, mushy spots, repot the plant in a container with drainage holes and a medium that is 1 part sand. Only water the snake plant when the soil is dry throughout the pot. If the roots are entirely brown and mushy, you won't be able to save your snake plant and should dispose of it.
Snake plants are susceptible to mealybug infestations. These slow moving pests use piercing mouthparts to suck plant sap. Mealybugs are grayish and resemble flattened pill bugs. White, waxy filaments cover them, giving them a cottony appearance. Mealybug damage includes wilting, yellowing and deformed leaves. Severe infestations cause leaf drop.
Controlling mealybugs with insecticides is difficult. The waxy filaments covering their bodies provide them with protection from chemicals and predators. Repeated applications of insecticidal soaps or horticultural oils are effective at killing its eggs and vulnerable, immature mealybugs. Wipe them off leaves with a soapy paper towel. For small infestations, dab each mealy bug with a cotton ball soaked in rubbing alcohol.