Normally, you can't place ExoticGarden "player heads" anywhere. Instead, you either eat them or, if your hunger is full, they return to your inventory. However, if you place them to the side of an empty cauldron, for some reason they would be placed down and then you can harvest them, which, if this was a "bush" type fruit/vegetable, would drop you a harvest and also create a bush on it's place, allowing you to duplicate bushes this way ("tree" type fruits don't place down saplings on their place, thus not duping)

Here's a video

Brewery ver. 3.11
ExoticGarden ver. DEV 78
Slimefun ver. RC 33
Paper 1.18.2