Journal February 8, 2018 - Semi-hydroponic orchid culture.

The topic at this month's meeting of the Northeastern New York orchid society meeting was growing orchids using a semi-hydroponic method. It is a simple inexpensive method of growing orchids and once the plant is established it is virtually impossible to overwater the plant, as it will be accustomed to growing in water.

You can use any container without holes in the bottom, however, I prefer clear plastic food containers so I can see what the roots are doing, and, more importantly, I can see when to water/feed.

Two 1/4" holes are drilled about 1" above the bottom of the container to form a well. Most growers use expanded clay pellets to grow the orchids, so that is what I am using as I also have a lot of them available.

The pellets are pre-moistened and added to the container so that it is a little more than half full before the plant is added. The plant is not adapted to growing in liquid yet, so you want any roots left on the plant to be above the bottom not touching the liquid.

It is best to start with a young plant that does not have a large established root system. Before placing the plant in the container any dead or damaged roots should be removed, as they will rot. The plant is placed in the container and the pellets are added to fill around the plant up to the brim.

At that point, I place a strip of tape over the holes and fill the container with a quarter strength nutrient solution and let the plant soak in the solution for an hour. After an hour I remove the tape and let the liquid drain from the container, leaving the remaining liquid in the well.
That's it, you are good to go. The pellets will wick liquid up to the plant from the well. When the liquid in the well is almost gone I replace it with more quarter strength nutrient solution and let it overflow. On every fourth cycle, I flush the container with clear tepid water to remove excess salts from the pellets.

As a trial, I have identical plants, one growing in bark and one being grown semi-hydroponically, and it should make for an interesting comparison.

There are a lot of videos on growing orchids using this method on youtube.com if you are interested in trying to grow orchids this way.