You can see I had the concept pretty well mapped out right from drawing 1. I did drawing 2 because I wasn't happy with the left character's right hand. I thought he needed to be indicating the plant and I also thought he should be moved a bit to the left. Turns out that hand was more challenging than expected - tough angle and I didn't know what I wanted. When I got to inking, I tried to draw it a few times over but honestly, I wasn't happy with any of them including the one you see. I did consider doing another rough but I felt I couldn't waste any more time on it so I just went with what was finished last.
The nurse has pretty funny hands and the shapes are nice. There probably should have been more medical type stuff around, an IV drip, perhaps a defibrillator, a bag of fertilizer, but again, time was an issue. Too bad, 'cause those elements would be funny.
But back to the first question. What did I learn?
Look at the difference between drawing 3 and 4. I should have been working and inking within a frame because as you can see some stuff got left out. Well, yes, only the medical chart got left out, but really, I think that detail is gold. Also, the whole thing feels a bit cramped. If I'd had a slightly larger frame, I could have pushed the man's word bubble up which would make it all less cramped.