You can't actually put anything except scalars into a hash or an array, so you have to put a reference to the array into the hash.

@b_griph = ('foo', 'bar');

%griph=('c' => \@c_griph,
        'b' => \@b_griph,
        'f' => \@f_griph,
        'o' => \@o_griph,
        'r' => \@r_griph,
        'm' => \@m_griph,
        'y' => \@y_griph,
        'g' => \@g_griph,
        'p' => \@p_griph,
        'w' => \@w_griph);

print "c = ",@{$griph{'c'}},"\n";
print "b = ",@{$griph{'b'}},"\n";
print "f = ",@{$griph{'f'}},"\n";
print "o = ",@{$griph{'o'}},"\n";
print "r = ",@{$griph{'r'}},"\n";
print "m = ",@{$griph{'m'}},"\n";
print "y = ",@{$griph{'y'}},"\n";
print "g = ",@{$griph{'g'}},"\n";
print "p = ",@{$griph{'p'}},"\n";
print "w = ",@{$griph{'w'}},"\n";

__END__
output
======
c =
b = foobar
f =
o =
r =
m =
y =
g =
p =
w =
[download]

by the way, the print code can be simplified to:

foreach $key (keys(%griph)) {
   print("$key = @{$griph{$key}}\n");
}
[download]

Data::Dumper is very useful for debugging:

use Data::Dumper;
print(Dumper(\%griph));
[download]