How to Build Mini Tropical Greenhouses

Purchase a rectangular storage container with a lid. A 33-quart container that is approximately 16 inches wide, 22 inches long and 8 inches deep works well. Smaller or larger containers may also be used as long as they are 6 inches deep or deeper to give the plants’ roots plenty of room for growth.

Purchase plastic sheeting that is an appropriate thickness for its intended use. Thicker plastic sheeting, such as 6 mil., is commonly used for outdoor greenhouses. Natural light levels are much lower indoors, even in very bright rooms. Use thin, clear plastic sheeting that will allow for light in an indoor mini greenhouse, especially if the tropical plants require high light exposure.

Drill or cut six to 10 1/8-inch holes in the bottom of the container. Space them evenly across the entire bottom of the container. Place the container lid upside down on the floor and set the container on top of the lid. The lid will act as a water catch basin.

Set the container in its intended location and fill it with potting mix to a depth of 7 inches. Adjust the depth of the soil according to the depth of the container. The soil should be approximately 1 inch below the top edge of the container. Use potting mix that drains well. Even tropical plants do not like potting mix that remains soggy and moist for too long.

Plant the tropical plants in the container. Space them far enough apart to allow for plenty of room for growth. Water the plants generously. This may take two applications of water as some potting mediums, such as peat-based mediums, may be difficult to wet thoroughly.

Cut the top hooks off of six to eight thick wire hangers. The wire should be pliable enough to bend into a U-shape and thick enough to hold the shape. Heavy gauge wire or 1/4-inch rigid but flexible plastic or metal tubing may also be used. Bend the wires into a U-shape and insert them into the potting mix vertically with the ends of the wires within the container at the edge of the potting mix to form the greenhouse frame. Insert one wire at each end of the container and four to six more in between. Space them evenly along the length of the container.

Drape the plastic sheeting over the wire frame. Adjust it so that the plastic just touches the floor on one side and both ends of the container. Leave an extra 2 to 3 inches of plastic sheeting on one side, lift that side of the container and slide the extra plastic underneath it to provide some resistance. Go around to the other side of the container and use a paint scraper or flat screw driver to push the plastic sheeting down in between the soil and inner wall of the container. Go back around to the other side and pull the edge of the plastic sheeting out from under the container. Trim off the extra 2 to 3 inches of length. Push the plastic into the container between the soil and container wall with a paint scraper or flat screw driver. Tuck the plastic into the container in the same manner at one end but leave the other end loose for access to the plants.