Most plants require light, soil and water to grow. There are a few that grow in thin air. One variety is called tillandsia or air plants. Tillandsia are members of the bromeliad family. There are two types of tillandsia, those with hard leaves and those with soft leaves. Both grow without the need for soil and aren't difficult to cultivate.
Put the plant on a steady surface. It can be a branch, another plant, wood, seashell or rock. The tillandsia should not move or wiggle. If it does it won't send out roots to attach itself. For starters attach the roots to the surface using fishing line, staples or super glue. If necessary to stabilize the plant attach a leave or two as well as the roots.
Place in bright light. The harder leaved tillandsia can take almost direct sunlight. Others with softer leaves prefer a shadier spot.
Keep the temperature between 50 to 60 degrees Fahrenheit during the night and upwards of 80 degrees during the day time. Some varieties that originated in hot climates like a desert don't mind temperatures approaching 100 degrees Fahrenheit.
Regulate the humidity to remain between 50 to 60 percent. The higher the temperature and humidity the more the air should circulate. Don't crowd the plants next to each other so air can move around them.
Fertilize with a water soluble acid fertilize without zinc, boron or copper. Dilute the fertilizer to 4 times what the label says and mist on the plants leaves every two weeks. Tillandsia absorbs nutrients and water through its leaves. The roots simply attach the plant to the growing surface.
Water by soaking the plant for 20 minutes.