Is it the database that is slow, or the Perl code?

You can set an environment variable (iirc it's DBIC_TRACE) to force DBIx::Class to show you its SQL queries. You can try them independently from DBIx::Class, and measure their timings

If it's actually the database that's slow, consider adding an index to the start_date column.

You can also let mysql explain the query execution plan to you, and see if it uses indexes for all operations. If not, you might have to add another index, or restructure your query in a way that mysql can optimize.

And finally, when you refer to the short form of DBIx::Class, plese use say dbic, not dbix - there are many DBI eXtension modules out there.