In reply to Alice Cheng.

Thanks for sharing your experience.
1) Yes, you could create an SG annotation data set. That is not how I prefer to work with SG graphs. If you want an example, as your question on SAS Support Communities.
2) Yes, add GROUP=Species.
3) OK. Sounds reasonable.
4) True. Also, reducing the font size might help.
5) OK. The POSITION= option also supports using a text variable with values like "top", "bottomright", and so on, but I think that might be hard to automate in a macro.
6) If you are using SAS 9.4, I am not familiar with recent changes to PROC SGPLOT that would help.
My closing statement is that you might be trying to use a graph to display information that is better displayed by using a table. Consider whether the ParameterEstimates table from PROC GLM might be more suitable to convey the information.