This is just a tiny first step: all I have is a program which takes a text specification of the plant, which can be thought of as a genome, and generates a geometric representation of the 'adult' plant. The specification still has to be written by hand (or, in this case, cribbed from Figure 1.24a of The Algorithmic Beauty of Plants), so I'm a long way from being able to actually evolve these plants.
The image quality is admittedly not great. I wrote the code to produce output in OBJ format (because it's dirt-simple to code for), but I've had difficulty finding an OBJ viewer that displays lines, as opposed to just polygons. The best I was able to come up with was to import it into Blender and then take a screenshot. Better output options are high on the priority list.
I know I haven't really explained what this is all about, but I wanted to record this right away. More context will have to wait for future posts. In the meantime, feel free to comment and ask questions- the more encouragement I get, the more I'm likely to write.