Self seeding flowers – to mulch or not to mulch? – Reddit Post

I live in Denver (hot and dry) and just planted this perennial flower garden. It has a lot of self seeding flowers – Shasta daisy, coneflower, delphiniums, foxglove, California poppys to name a few. Then I also have some ground cover that I want to spread as well. Ideally in 2-4 years I don’t want to see the ground at all. I want this garden busting at the effing seams.

So my question is.. should I mulch? I want to do a light layer of mulch to help retain moisture but I don’t want it to hinder the self seeding process. Thoughts and advice welcomed please!