When is too late to rush?

My first opportunity to go through formal recruitment will be when I am a senior. I have attended the same university all four years, but I did not go through recruitment my freshman or sophomore years.

And my junior year (When I realized that I REALLY wanted to go through rush), I was studying abroad and unable to participate. I do not go to an extremely competitive school- we have only 4 sororities.

But, as a senior. Graduating in (hopefully) May... Is it too late for me?

Honesty Appreciated