Answer: In general, annuals and vegetables are easier to raise from seed than perennials. You may have more competition in bedding plant sales so you might consider some of the more unusual annual flowers and possibly some herbs and/or heirloom varieties of vegetables. You might look at the table at the following site which supplies some typical time frames in weeks and see which ones appeal to you. http://muextension.missouri.edu/xplor/agguides/hort/g06570.h...
You might research more specific information about individual plants at the following searchable site: http://plantfacts.ohio-state.edu/
Good luck with your plant sale!
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