As many gardeners already know, there are a myriad of cold frame and mini greenhouse designs and sizes available online. Recently, our co-author (John L. Dose) wrote a piece on a similar topic, DIY Greenhouse and Cold Frame. My spin on this theme will examine my recent experience with a decent mini-greenhouse purchased on-line from Quictent.

The overall design of this structure is pretty good however, a few improvements are in order. Once the panels are zippered shut, there is no possibility of cross ventilation since the side panels are not vented. In the early spring, in Zone 6, this can prove fatal to young seedlings. The enclosed structure does an excellent job of staying warm and will get pretty hot on a 50 F degree day with good sunlight. Hence, if the grower isn’t close by to vent the front panels, he or she runs the risk of damaging young seedlings. I’m going to insert two side vents to remedy this matter. The other concern deals with securing the structure to the ground. Tent spikes are not provided to achieve this end. Thus, a trip to a local vendor needs to be done before setting sail (literally).
Overall, I do recommend their growing structure as it goes up easy and is easily packed away between uses. It also serves to harden off seedlings when transitioning plants from the greenhouse to the field. In a manner of speaking, the mini-greenhouse (MG) design serves a similar function as a cold frame. Next season, 2023, we will build a cold frame (CF) and place the MG on top of the wood frame. The dimensions of the CF will equal the dimensions of the MG’s perimeter. This will permit us to secure the base of the MG to the top of the CF. (More on this development in 2023).