Originally Posted by Mark Oomkes
And anyone applying 3" of mulch every year is ignorant. Should be an inch at most. At least by me.
Until people stop thinking of mulch as decorative instead of functional there will always be a problem here.
Apply 3-4 inches of bark in the appropriate areas (i.e. per plant requirements) to get all the benefits you mentioned ... reduced evaporative losses, reduced soil temperature, reduced erosion. reduced weeds, organic matter inputs, etc ....
Renew your bark only when it thins ... not every year, and certainly not remove and replace every 3 years.
In my area, a redwood chipped bark at this application depth will last 5+ years before thinning to the point where more is needed (i.e. increased incidence of weeds and/or exposed soil).
The only organic mulch i really do not like is gorilla hair shredded bark.