This thing is great. This was our first try with any kind of greenhouse and it's going well. The design of this is basic, but that's to be expected for what it is. It took 10 minutes to assemble and everything is just press-fittings, so no tools needed. I recommend using a zip tie to affix the center of each grate/rack to the support rods. The racks are bowed upward when they arrive and the zip tie flattens this out and keeps the racks from moving.
We got this so we could get a jump on our garden, and started our plants in mid April in New Hampshire. We can't plant in the ground until mid-late May. I put 60 plantable pots (about 12oz size) in and they fit easily. With 3 plants in each we have 180 starters for our garden. This seems to have been a pretty optimal packing density for this size greenhouse. It's allowing plenty of light down to the lower shelves, while still making good use of the growing area. Periodically rotate plants top to bottom for even sunlight.
Watering is easy as this has an open bottom. Temperature stability is something you need to monitor with this design. It's not a flaw with the unit, it's just a consequence of it being so small. The temperature can rise quickly in the sun and exceed the maximum levels for your plants. Likewise, it can drop quickly to ambient temperature if the weather turns cloudy on a cool day. I bought an affordable bluetooth thermometer/hygrometer so monitor its status from inside the house. In full sun on a 65 degree day the inside temp will exceed 100 degrees at which point I unzip the access flap and use a log to keep it in place. Effectively this gives you two full-height slats to regulate temperature. This works well, so if you're not going to be home all day to monitor it and warm temps / sun are in the forecast, just unzip it and secure the flap in place to keep it working well. If the forecast calls for cooler temps or no sun, go ahead and leave it zipped closed.
That brings me to the drawback to this small and simple design. If you live in a climate that sees freezing or near-freezing temps in the spring, you're going to need to move the greenhouse inside or arrange a heating solution. The temp will quickly fall to ambient when the sun goes down and your plants will die. I carry it into the garage for cold nights. You'll need decent upper body strength for this, as it can get heavy when loaded and it's awkward to carry without toppling plants. If you're going to carry it I also recommend using rope or bungees to secure the levels together. The press-fittings can come apart when you lift it loaded. I think a better way might be something like a safe heater on a timer, but I haven't experimented.
Wind is another consideration. Find something sturdy in a sunny location and bungee or ratchet strap it to that something. This WILL blow over and ruin your plants if you don't do this.
Overall it s a great design for its intended use and its drawbacks can be overcome pretty easily.
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