Generally mulch usually decays to a brownish color, but then it's the components that you should think about. Some mulch robs the soil of nitrogen so you may have to add some fertilizer in the future depending on what plants you are mulching but all in all it is safe. You might want to contact cooperative extension and get your soil tested to see what you might need to the soil to reach its optimum potential, again depending on what plants you have.

Here is a link that might be useful: Propagating Perennials

I can see little advantage in using the brown-dyed mulch. As Bullthistle says, most mulch ages to a brown color anyway - the dyed one, I think, stays a darker brown over the season, but there is little difference in the long run.

I do know that the black mulch, esp. if bought when freshly dyed, will come off on gloves and clothing, and is fairly permanent - I helped a friend spread some at their house. I worry enough about unwanted stuff in my soil that I would be reluctant to add anything I didn't HAVE to.

Getting a soil test is a good idea, in general. However, as long as you aren't using very freshly chipped material (say within the past month or so), there should be no leaching of nitrogen from the soil, except possibly at the interface of the mulch and the soil surface. This is usually not enough to worry about, especially if you are using aged mulch products.

I think she's talking about the mulch that's dyed red, brown or black to retain its color instead of fading to the pale silvery color that wood mulch typically fades to. I don't know- i personally don't like it (esp the red), but that's just me. No justification- just don't like how it looks.

If rggarden is referring to the red/brown rubber-dyed material that never decays that's made from old tires ... it's probably not a good idea from what I've heard. If this is the kind you mean I'd google it and do a bit of research first.

No- there's dyed hardwood mulch available, too. That rubber mulch is wonderful for playgrounds, so springy and soft, but i sure wouldn't want it in a landscape.