When is a new sourdough starter finished

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I have been making a starter as described in the handbook. It appears to be successful. How do I know when it is "ready" to put away in the fridge? I began about 14 Feb.

Your starter is not quite mature, but it will be in a week or so now.  However you can try making bread with it now and store it in the refrigerator, if you are tired of seeing it out on the counter-top,  If it is 100% hydration or less, it should double in about 2 hours at 80 to 85°F.  

Ford