Mulch is a given for most experienced vegetable gardeners. It cools the soil, retains moisture, smothers weeds, and when it breaks down, adds organic matter to the soil.  I’ve tried a few different types in my day, and wanted to spout some old guy opinions.

Hay: Love the smell and the ability to cover a large area with an armload.  With hay straight from the bale, normally the individual pieces are so long that after time, the more persistent weeds will find their way into the light.  If I use hay, I’ve learned to run over it a few times with a mower.  A shredder would do the same or better.  Of course that makes the pieces smaller and gives better coverage, but also dramatically increases the amount of hay I need. It’s not free in my case. That being said, shredded hay, when it’s free, makes a beautiful mulch.