Since feeds in ikiwiki are just the result of the [[inline]] directive generation a list of pages, you can use the combination of a pagespec and the tag plugin to stop ikiwiki from syndicating draft pages. Just include “!tagged(draft)” in your page spec for the page that generates the feed (e.g. blog.mdwn):

[[!inline  pages="./blog/* and !*/Discussion and !tagged(draft)" show="100" ]]

then for each article you’d like to hide for now, simply add the ‘draft’ tag:

[[!tag  foo bar baz draft]]