Use a mannequin head as a pot
If you have a friend who is passionate about plants, we have a gift that will make them as excited as one can get. This is a plant-shaped crown for your mannequin we’re talking about, so be serious. It’ll make its head explode, quite literally, because you need to take the brains out first.
It makes a perfect place for ferns or ivy; the leaves will look like the mannequin’s hair. Every time your friend has to trim the dry leaves or water, it would be almost like a visit to the hairdresser for the planter. You could even suggest the start of a new salon for plants.