I’m going to address this simply from the point of view of community theater.  The time needed for college or professional productions probably differs.  I’m also starting with choices that are largely made by the director, but I’ll finish with how it impacts you as an actor.  If you can identify upfront that the director may not have given you enough time to rehearse, you can handle how you rehearse a little differently to overcome this deficit.

In community theater, time is your best friend, but I don’t mean just the number of hours you spend in rehearsal.  Yes, that matters.  But the number of weeks from the first reading to opening night matters as well.

Why?  Because it gives your subconscious time to do its thing.  This is what John Cleese talks about when he says the third requirement for creativity is Time.  Ideally, you want seven weeks of regular rehearsals and one week of technical rehearsals.  Let’s say it takes you five weeks to get off book.  That gives you one week to REALLY get off book; that is, to reach the point where the words come out without you having to think about them.  It gives you one more week to do the fine-tuning that can only happen once you are REALLY off book.  And it gives you the eighth week to adjust to technical issues.

If the entire cast can get off book in four weeks and you’ve got a compelling reason to not use an eight week period, then for an “ordinary show” (see below), you can shorten the rehearsal period to seven weeks.  However, it’s my experience that at least some of the cast will still be on-book in that fifth week.  But the theory here is that you should put the script down no later than three weeks before opening night in order to benefit from what I will call the “subconscious effect.”

Has there ever been a community theater production you’ve been part of that seemed to be noticeably better on the second weekend of performances?  If so, you’re looking at the “subconscious effect”.  Once you get off book and are “fine-tuning” your performance, your subconscious gets very busy and does work on your role that you aren’t aware of.  Even if all you do in the week after opening is look at your script three times and have one pick-up rehearsal, your subconscious is still working and getting more comfortable with your choices.  Magical stuff happens when you give it this time to work.  So if you can give it that extra week before opening night, you’ll get better buzz to help fill the house on the second weekend!

As for the number of hours you need, my general rule of thumb is that a production with no special needs that will run for 2 hours including one 15-minute intermission requires 54 hours of rehearsal time prior to Tech Week.  To get the most out of this time, you need rehearsals that last at least 2½ hours long, three or four times a week.  (Rehearse them more often than that, and they have no time to work on their part at home as well as do their laundry.)

If the play is longer or shorter than two hours, you can adjust the total rehearsal time up or down.  But length is not the only consideration in choosing the number of hours for rehearsal.  Special considerations can increase the amount of time you need to work outside of rehearsals as well.

What do I mean by special considerations?  I’ll talk about them next time . . .