Fill a large clear plastic or glass container full of tepid tap water. Growing orchids in a water culture is easier in a clear container because it allows light to penetrate the orchid.
Place a stem from an orchid into the water. The container should be deep enough to accommodate a significant amount of root growth.
Put fertilizer into the water regularly, as you would feed a normal orchid plant. Check the manufacturer’s instructions to find out how regularly and how much fertilizer you should add to the water.
Change the water every week. Replace the old water with new tepid tap water. Adding water that is hot or cold could shock the developing plant.
Keep the plant in the sunlight as you would a normal plant to allow it to grow.
Repot the root system in a larger container of water when it has grown too large to be accommodated by the first container.