You are looking up the hash keys "colour.red" and "colour.blue". Use one of the following instead:

print $hash{$t."red"};
print $hash{"${t}blue"};

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P.S. You just posted that you figured it out - it's best to also post your solution for the benefit of others.

In reply to Re: Concatenating strings to use in a hash.. by Anonymous Monk
in thread Concatenating strings to use in a hash.. by Anonymous Monk

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