How to Pick the Best Mulch for Your Mountain West Garden Beds

Since entering horticulture professionally over a decade ago, I’ve noticed a correlation on the Colorado Front Range between wood mulch (also called arborist chips) and water-wise gardens. A beautifully designed garden goes in, with appropriate irrigation and plant palette, and the garden looks great—briefly—before languishing. Plants in these beds never quite take off, or they fail before their natural lifespans are over. I casually refer to this as plant/mulch mismatch, and it’s an issue I see too often, maybe because mulch is anything but exciting to the average homeowner.

To get to the bottom of why these mulch mistakes are happening in the Mountain West, I spoke to expert horticulturists from across the region. I asked the following questions: “What mulch do you recommend to gardeners in your area for use around trees and shrubs?” “What about a ‘classic’ perennial bed?” “What mulch do you recommend for a water-wise or native-heavy garden?”

I gathered the insights below from interviews with Robb Smith, Nich Boynton-Steele, Guy Banner, Lauren Carvalho, Michael Guidi, and Jacob Mares, who practice in northern New Mexico; the Colorado Front Range; southern Wyoming; Salt Lake City, Utah; and Boise, Idaho.

Mulch mismatch was least pronounced in Boise, where it seems that all kinds of plantings do well with the quality of arborist chip mulch available in the area. This included everything from xeric, native plants to trees and shrubs. I’ve discussed the absence of mulch/plant mismatch with experts in the area and, frankly, none of us are completely sure why they don’t experience it. Regardless, it makes selecting an appropriate mulch an easy exercise for the Treasure Valley and surrounding areas. Mulch/plant mismatch