You can use almost any cabinet! People are using Ikea's cabinets because they just happen to have a lot of great options. I'm using Ikea's Detolf cabinet in white.
You'll want full-spectrum LED grow lights. The ones I use come with three light strips attached to one wire—perfect for multiple shelves!
Weather stripping is essential. Weather stripping will close gaps in the cabinet and create the environment your humidity-loving plants crave!
Even humidity-loving plants don't like 24/7 muggy conditions. Air flow is important. Setting up one or two mini fans in your Ikea greenhouse cabinet can help.
I find my greenhouse's humidity gets high enough on its own, but some people like to set up a mini humidifier in their greenhouse.
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