Seems to be still an issue. Might be intentional because of the germ situation but I need them for my Drekos. I tried your solution by copying the Leafy Plant seed entry and changing it to Swamp Lily so hopefully it'll work next time.
As described. Spent days (in game) trying to figure our why nobody would do advanced research. Turns out they couldn't get to my pitcher pump and there was no indication on the Super Computer that it needed water.