I want to lay mulch down around my already established plants to help retain moisture and discourage weeds. Is there a recommended material for this? Or at least some materials I should know to avoid?
Update: The choices I'm looking at right now are hardwood, cedar, and cypress (all available from my local Lowes/Home Depot/etc and are pretty cheap. Also, my city has a program that gathers wood that people are throwing away and shreds them into mulch. It's free to take some and they'll fill up the back of your truck for you as many times as you want. You end up with a random collection of wood...not sure if this really matters though.