A hoop greenhouse is a fast, inexpensive greenhouse for home gardening. These greenhouses are typically constructed with inexpensive materials for short-term gardening. The houses can be left unheated, or heated with portable heaters. Hoop houses can be assembled quickly, and taken down just as rapidly. A hoop house can be used in fall and spring to extend the gardening season. In winter hoop houses can be used to grow cold-season vegetables such as broccoli and lettuce. Construction of hoop houses is simple.
Lay out the footprint of your greenhouse using a garden hose. A typical hoop house is 12 feet wide. For the purposes of this article, the hoop house will be 24 feet long with 4 feet between each greenhouse support. To build a longer hoop house, add more supports along the length of the greenhouse.
Pound six rebar stakes halfway into the ground down one side of your greenhouse with a rubber mallet. Align the other six stakes down the other side of the greenhouse, across from the first set.
Cut a 24-foot-long board in half. Place each half-board at the ends of your greenhouse. Place the remaining two boards along the sides of the greenhouse just inside the rebar stakes so that the board ends around where the half-boards end. Nail the boards to one another where they touch.
Slide the ends of the 24-foot conduit pipe over the rebar stakes where they emerge down one side of the greenhouse. Flex the conduit pipe into an arch and slide the other ends over the stakes on the other side of the greenhouse.
Run a length of wire over the center arch of the pipes to create a ridge over the greenhouse. This will make the greenhouse more stable. Wrap each piece of conduit with one turn of the wire.
Cover the shell of the greenhouse with PVC greenhouse plastic. Staple the plastic along the sides with carpenter's staples. Weigh down the ends with rocks so that you can pull the plastic back on warm days, to vent the greenhouse.