The kapok tree can grow up to 60–70 meters tall and can reach even above the canopy of the rainforest. Strong buttress roots hold the huge trunk firmly upright even in strong winds. Trees with buttress roots are particularly abundant in rainforests, where they effectively bind the soil and thus prevent erosion.  

Fully grown kapok trees produce several hundred seed pods each year. The fiber that forms around the seed pod is hollow and airy, and does not absorb water. The fiber has been used as a filler in lifebuoys, furniture, pillows and blankets, as well as insulation.  
 
Oil pressed from the seeds is used as lamp oil and for making soap. The wood is used to make matches and canoes. Young fruits and shoots can be used for food. A boiled extract of the tree's bark has been used to remove fluid from the body (i.e., as a diuretic), to increase libido, treat headaches, and treat type 2 diabetes.