South Florida Orchid Society

by Susan Taylor
Originally published in BellaOnline

Many orchid growers graduate from the windowsill to a terrarium in order to better control environmental conditions, especially humidity, for their plants. An old aquarium can be used for this purpose fairly easily. If it was a fresh water tank, all it needs is a good cleaning with soap and water and an overnight soak in a bleach solution to kill any algae left in crevices. If it was a salt water tank, you will need to fill the tank with water and let it soak for several days, rinse and soak again, in order to make sure that all salt residues have been removed.

Although it is not very natural looking, most experts recommend using egg shell crate (material used for fluorescent light covering available at most hardware stores). This material is approximately ½ inch or 2 centimeters high with openings in squares of approximately ¼ inch or 1 centimeter. The effect when this is used as the substrate is then to keep all materials from the bottom of the terrarium while holding water and allowing it to evaporate up through the spaces.

You will want to choose props much like those used in a fish tank in order to make the whole thing look natural. Drift wood, rocks, cork are all good choices. Be sure that you clean and sterilize anything that you bring in from the wild. Materials purchased from pet stores are probably already sterile and will not need to be treated. Place your props, the largest in the background and smallest in the front before you put in your plants.

Plants should be chosen carefully for size and the larger plants can be placed in the back or growing up cork. Small plants such as Masdevallia, Pleurothallis and the smaller Paph species are good choices. Jewel orchids should always be considered since their foliage is always interesting when nothing else is blooming. Choose contrasting leaf colors for the best effect. Ferns make very good companion plants and will add a pleasing texture change to the scene.

Place your plants still in their pots and then add sphagnum moss around the plants and cover the egg crate so that it no longer shows. When assembled like this repotting is very simple – just take out the plant and pot, put in new media and then replace. Some orchids will tend to grow into their environment and should not need repotting if they have acclimated such as growing on a cork backdrop.

by Susan Taylor
Originally published in BellaOnline

A decorative idea for growing orchids in the home is the use of a terrarium, conservatory or Wardian Case. The concept behind the use of these items is that you create a  mini-greenhouse inside to grow plants. They come in all sizes, colors and shapes to suit almost any décor. It is important to understand what will and will not work for orchids in this type of environment. The major thing to remember is that we are trying to replicate the growing conditions for the orchids we are putting in the chamber. Thus, high humidity, good air circulation and adequate lighting are required.

Terrariums by definition are self-contained ecosystems designed to live without disturbance for a year or more. The water in the container is constantly re-circulated by evaporating and dripping back into the soil or growing medium. Most orchids will not survive well in this kind of an environment because they need more air circulation or they will rot.

A Conservatory or Wardian Case is actually a mini-greenhouse with air vents, perhaps fans, lights, everything necessary to grow indoors. There are any number of combinations that can be used, depending upon your needs. The Orchidarium site has the most complete information I’ve seen, including what accessories are available. If you are considering building your own there are several really good articles available. The Do It Yourself Wardian Case article by Prem Subrahmanyam published in the Tallahassee Orchid Society Newsletter is extremely helpful and detailed.

In corresponding with several people who have successfully grown orchids in enclosed gardens, the primary comments were that it is necessary to have fans going 24/7, keep an opening to allow in fresh air, and to choose orchids which prefer high humidity, have lower light requirements and like the warmer end of the growing spectrum. It is extremely difficult to provide cool temperatures in enclosed spaces while using artificial lighting. One lady even mentioned trying to reduce evening temperatures by putting ice in the bottom of the enclosure, but found that that didn’t work adequately. And, most importantly do not have pots or plants sitting in water!

It is important to have automated controls on a Wardian Case because it doesn’t take much to cause conditions that will kill your plants. In order to keep the humidity up while the lights are on, misters are  recommended. It is recommended that lights be used for 12-14 per day. Recommended orchids mentioned were Pleurothallids although Masdevallias don’t seem to like it as much as the Restrepias and mini-Dendrobiums.

One thing that I didn’t hear much about, but I would recommend is that you try mounted plants in a Wardian Case, especially if you are looking for a decorative display. Mounted plants need higher humidity to allow their roots to gather water than those in pots.