A greenhouse is great for starting off young seedlings or growing plants year-round. By utilizing transparent barriers around the greenhouse framework, solar radiation is allowed to enter the greenhouse (heating it up) while retaining heat and moisture needed for optimal plant growth. Here’s how to build a simple, and cheap, mini-greenhouse using an old shelving unit and clear polycarbonate roofing material.
Start with a tall (72” high) 3 foot by 2 foot plastic (or metal) shelving unit. If you don’t already have one, they can be purchased cheaply from your local hardware store.
Stand the shelf on level ground in the spot that you wish it to be permanently located. Place patio stones around the legs, keeping them as close together as possible, while allowing a “hole” for the shelving unit’s legs. You can also use a single patio stone and drill a hole through the center of it if you’d like.
Remove the shelf from atop the patio stones and drive four 2 ½ foot rebar into the ground through the holes between the patio stones. Place the shelf unit back into place by sliding the legs over the rebar.
Polycarb roofing panels, commonly used to cover and shade patios, can be purchased from any hardware store. Cut transparent polycarb panels to size. You will need polycarbonate pieces for the back, sides, top, and front of the shelving unit.
Drill pilot holes in the shelving unit frame and attach the polycarb sheets to the shelving unit with screws. You may fashion a door in the front of the unit or loosely attach the front panel to the shelf unit so it can be easily lifted off and removed when you need to get to the plants.