Should I ask her out again after some time?

I've worked with this girl for the past year or so and never really spoke to her. About 2 months ago she starts talking to me, offers her number and we flirt or atleast what I perceive as flirting. I felt there was something there considering the fact the she never said anything beyond "hi" to me before. I finally got a chance to ask her out, i casually asked her "hey what would you say to the two of us going out sometime?" She replied that she's going to be really busy over the summer and won't have time for anything else. Normally I would just take it as a no, and walk. However I believe her because she does work 3 jobs, one with me, she's a consultant and a freelance photographer and the summers are really busy for photography due to weddings. So that's all she said. I was thinking about playing it cool and perhaps asking her out again once the summers over and things slow down. Should I? Or should I take it as her being polite and saying no and just move on?