Changing number of category posts

Hey there.
I’m trying to change my client’s blog page to feature all blog posts, rather than just the latest ten:
http://www.bellaandbhakti.com/category/heartfelt-musings/
I’m posting using the category, rather than a page or posts page and I’m trying to find where in the editor I can change the number of featured category posts to make it infinite.
Any ideas?