When you are dealing with a short growing season, a cooler climate, or an unseasonably cool or short summer, a greenhouse can be a real lifesaver. But what if you are temporarily cashless, or living in a condo, or are a renter with a landlord who won't allow you to build a regular greenhouse? Enter the mini greenhouse!
This is a picture of a makeshift greenhouse that I have set up outside my front door. It is about 3 feet wide, 6 feet tall, and 2 feet deep. It was extremely easy to assemble. I bought it at Home Depot for around $60. It breaks down easily for moving, and although it is fairly lightweight when the shelves are empty, I've found it to be very sturdy for a plastic shelf.
If you wanted to make it more moveable, you could buy the heavy-duty metal shelving units on wheels that I've seen at Sam's Club. That way, if you're using it for seedlings in early spring, and there's a forecast for a hard frost, you can wheel it into your garage.
Make sure the wheels can be locked, and that the shelves can hold a LOT of weight, in case you end up doing heavier potted plants in the future.
The plastic cover is a thin mattress protector bag meant to protect your mattresses when you are moving. I'm not sure what size it is, but it has to be either a king size or a twin...I'm thinking it's the twin. It just barely fits over the shelves. Ideally, if you could get ahold of greenhouse sheeting, that would be the longest lasting and most efficient...and also the priciest. I had planned on using 6 or 8 mil plastic sheeting from Home Depot's paint department, until I came across the mattress cover.
If you use a roll of plastic sheeting, you'll need some way to attach it to the "greenhouse". You could use some kind of clamps, or duct tape. The way I have it configured, the top shelf can't be used, but if you could come up with some way to raise the plastic off the top shelf, it could be used. The total cost for this greenhouse was about $60, the cost of the shelves. If you buy the plastic sheeting, it will cost about $10-20 extra, depending on how small a roll your store sells, and what their prices run. If you have the plastic already and can scrounge up some cheap used shelves, it could be as little as $5-10. Or free, if you use free wooden pallets and build your own shelves!
Eventually I'm going to build a greenhouse in a panelized fashion, so it can be easily disassembled and moved. In the meantime, this seems to be working very well. Check out the video for more details, and how my seedlings are doing in the greenhouse.
If you enjoyed the video, please leave a comment, and feel free to let me know what subjects you'd like to see covered in any future videos!
This unit is similar to mine:
Remember, you want heavy duty shelves that hold a lot of weight, even if you're not using it to capacity.
Here are some choices for plastic covering:
Here is a complete mini-greenhouse, but it's not sturdy, so I wouldn't recommend it except maybe for a sheltered porch or balcony, out of the wind:
Here are some clips to keep the plastic wrapped around the shelves:
But it's better if you can scrounge these components for free, from what you already have. Good luck!