Between a cold frame and a green house

For the last few years, my friend Tony Barton has tried to come up with a design for something like a greenhouse or cold frame, in order to extend the gardening season. He wanted it to be inexpensive and simple to build as well as portable. After experimenting for a while, he eventually came up with this hoop house which answers all his requirements.

Hoop house

I wanted to built one for myself but, not having the equipment to drill the required holes in the wooden base (see below), Tony volunteered to help me with these.  Then,on second thought, he decided to give me one of his, since over the last few years he has built several and cannot use them all!

The design is very simple. At the base is a rectangle of rough-cut cedar. Holes have been drilled on the long sides of that wooden base to accommodate the end of PVC pipes which are bent over the frame to make a hoop. 

The end of each hoop fits in a piece of rough cedar timber

You do not need straps to hold the PVC pipes, neither do you need any connecting joints as each rib is made up of a single 10 foot PVC piece. There is a small board at the top inside to which the hoops/pipes are tied to keep them in place with respect to one another.

Board at the top keeps the hoops evenly spaced

 The whole thing is covered with plastic, except for an opening at each end covered with a piece of plywood that acts as a door and a vent.  It does not need hinges or latches. At this time of the year, the "door" is open in day time and on sunny days the inside temperature remains around 30 C with one door/vent open.

It is not particularly elegant, but it is most useful and practical.

Like greenhouses and cold frames it allows you to extend the gardening season or to grow things that require more heat than you normally get. In my case I can use it in summer to grow crops for which the garden is not hot enough. It also allows you to grow greens earlier and later in the season. 

Basil seedlings grown directly in the ground

Plants are grown directly in the ground in the hoop house. My cold frame and the shed with a translucent roof I use as a green house have floors made of stones and gravel, and plants in them have to be grown in pots. 

 

Plants are grown in containers in the cold frame

The whole hoop house can easily be moved by two people. Being built of cedar and PVC, it is very light, even if it is big and stable enough to stay put in a strong wind. The possibility of moving it is important to me, because once it is set in once place for a season, I put a lot of compost and improve the soil inside it as much as I can. Then the next year I move it to a different spot in the garden where in turn the soil gets improved. 

It is not as large as a greenhouse, but bigger than a cold frame. This means that the volume of air inside it heats up and cools down less fast than in a cold frame and faster than a greenhouse. It seems a happy medium for what I use it for. It measures 4 by 8 feet and costs about $150 to build. It is in its 3rd year. I expect to have to change the plastic covering next spring. The only drawback I find is that it is not high enough to stand up in it (someone suggested it was, in fact, a stoop house).