You don't need this part , delete it, and it should just work 

# New site
$h{'siteA'} = {'09-10-2011' => 1};

[download]

Its called autovivification, it means if you use it like a hash ref it magically becomes a hashref.

See References quick reference, autovivification, perlglossary#autovivification, autovivification

In reply to Re: Adding to a hash reference by Anonymous Monk
in thread Adding to a hash reference by Anonymous Monk

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