Try setting $/ = '';. 

#! perl -slw
use strict;

$/ = ''; # paragraph mode

print "'$_'" while <DATA>;

__DATA__
abc:
  asdf1
  asdf2

def:
  asdf3

ghi:
  asdf4
  asdf5

[download]

Prints 

c:\test>junk
'abc:
  asdf1
  asdf2

'
'def:
  asdf3

'
'ghi:
  asdf4
  asdf5

'

[download]

Setting $/ = "\n\n"; would also work for your data if there is exactly one 'blank line' between the paragraphs, but the magical setting of $/ = ''; is more flexible.

Note this quote from perlvar

Setting it to "\n\n" means something slightly different than setting to "", if the file contains consecutive empty lines. Setting to "" will treat two or more consecutive empty lines as a single empty line. Setting to "\n\n" will blindly assume that the next input character belongs to the next paragraph, even if it's a newline.
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: How to split into paragraphs? by BrowserUk
in thread How to split into paragraphs? by jrw

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