It is remarkable what can be done with natural fabrics such as cotton these days. You mentioned a blend, and it could be that the weaver used polyester to give the woven fabric its wrinkle resistant quality. If so, if you're careful, you should be able to press an edge to the pleats, but you may want to avoiding starch. If the fabric obtained its wash and wear wrinkle-free features by treating with enzymes (an expensive, but very effective method), starch will degrade these qualities.