Interesting topic.
Like most NPC orgs, AEPhi has no rules regarding color of letters. I myself have several floral patterns, and I've seen star prints, cow prints, tie-dye, leopard print, as well as solid letters in a variety of colors other than green and white.
My local sorority had a tradition of "sister shirts" that you got right after initiation. Alternating class years got either green letters on purple shirts or purple letters on green shirts. So everyone had at least one shirt in the sorority's colors. Other than that, though, the sky was the limit.
Another question for NPHC members - Do you view it as stepping on your toes when a non-NPHC org shares your colors? e.g., Alpha Phi Alpha and Kappa Alpha Theta both use black and gold. (Not that anyone would mistake a Theta for an APhiA or vice versa...
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