Greenhab is humid

That's good! Plants love warm, humid conditions. At least the ones I'll be growing. I had in fact cultivated some seedlings in anticipation and have now transplanted them into the soil of greenhab. It was really rewarding to see the water injection system working for the first time. Depress the plunger up by the compressor, then inside the habitat a moment later there's a brief spray of water. 

While there's condensation (which is weird to see underwater) it means there's enough moisture in the habitat for the time being. The constant throughput of dry air eventually carries it all away, at which point the condensation vanishes, my cue to inject more water. I didn't think doing this with plants would be so interesting, but it already is.

One possible implication is that in any hypothetical undersea colony, the plants and humans should be kept in separate habitats, or the module with plants should be separated from the rest with a humidity barrier as ideal conditions for plants differ greatly from ideal conditions for humans.