Temporary Greenhouse

Lots of folks would love to have plant protection during the fall and winter months. A greenhouse is the ideal solution for overwintering tender or tropical plants. The problem is that many just can't or don't want to have a permanent greenhouse. Building a temporary greenhouse is a pretty easy and inexpensive solution to this problem.

I have always needed a way to store my plumerias over the late fall and winter months. Previously I had to un-pot all of my plumerias in the early fall and allow them to remain dry and partially soilless outside (under oak trees) for a few weeks so that they began to go dormant and to lose a good portion of their leaves. Then I would remove the leaves that remained, rinse off all the remaining potting soil, and bag them in large commercial plastic bags. Then I would clear out a guest bedroom closet and store those bags of plants until spring. This worked OK, but my wife never was comfortable having bags of plants in "her" closet. Also, because they were completely dormant for 4-5 months, I would always lose a few plants. Another downside of this technique was my having to re-pot all those dozens of plants and then having a lag time for them to show growth.

The solution to this was to leave those plumerias in their pots, and though they still would either go dormant or semi-dormant, all that was necessary in the spring was to get them outside in some sun and begin watering. Thus, the need for a temporary greenhouse.

The first decision to be made was where to put this temporary greenhouse. People build them in their yards, on their decks, or on their patios, but the problem in doing so is having the greenhouse strong enough and having it anchored well enough so that high winds won't destroy it or take it away. This was a problem for me. My solution was to build this structure inside my garage. The same can be done for those with carports, barns, or large storage sheds.

I had a space about 6' wide and 10' long along one side of my garage. There was even a window in this area, which I took better advantage of the second year. Since there would never be an issue with wind, the frame would not have to be terribly strong, and certainly no anchorage would be necessary. I decided to build the base of the frame out of 2x4' and the rest of the frame out of 2x2' lumber. The covering would hide all the wood from view, and thus less expensive, "secondary" lumber could be used. Rather than nailing the framework together, I used screws. I wanted to be able to disassemble the greenhouse in the spring, storing the lumber to be used the following year. Since I had already used solar blanket material as secondary covers for my two permanent greenhouses, I decided to use a lighter gauge of solar blanket material for the temporary greenhouse. I used 14g, though 12g material would have worked as well and would have saved me a few bucks. I cut the solar blanket material to fit the two sides, one end, and the top and then stapled the blanket material to the wood. I cut out a piece of blanket to cover the (walk-in) end, stapling the top to the wood. I stapled several Velcro strips down each side of that opening and glued Velcro strips to the blanket material to correspond with those stapled strips. That allowed me to close that end with Velcro and roll up the blanket material when the weather was mild.

Since solar blanket material keeps cold out and holds warmth in so well, I put the smallest, 750W electric heater I had to keep the space above 50F. This small heater was more than adequate and its thermostat had to be set at just about its lowest temperature.

This year I expanded the length about 2' and now the window exposes the greenhouse to additional light. I have been very happy with this temporary greenhouse.

10/30/14

11/05/15