Best mulch option - Ask Extension
Hello. I will be mulching my yard in the next few weeks and wondered which mulch you recommend for pop up sprinklers. I have read in most places that...
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Best mulch option #926024
Asked March 14, 2026, 12:54 PM EDT
Hello. I will be mulching my yard in the next few weeks and wondered which mulch you recommend for pop up sprinklers. I have read in most places that gorilla mulch is best, for CO but I worry about the water penetrating the mulch in my beds. I have found in the past that the earth remains dry under the layer of gorilla mulch. It is possible that the layer was too thick, but I still have concerns. Thanks for your help.
Denver County Colorado
Expert Response
Which mulch you choose is really dependent on the purpose of the mulch and what you are growing.
If the areas you're mulching are trees, shrubs or perennial beds, gorilla hair mulch would be okay, as are other options. Since you have pop-up sprinklers, the depth of the mulch is a concern since gorilla mulch does eventually form a mat which will hinder water from penetrating. This mulch is recommended for slopes and high-wind areas, since it stays in place. To get more penetration to the soil, use a more coarse mulch (bigger pieces) that don't form mats and allow better soil penetration.
You may want to consider grass clippings or leaves which are not as resistant to water, or less depth of whatever wood mulch you prefer.
Also, native perennials prefer small-sized gravel and rock, so that native flower and shrub stems don't rot from too much water.
I'm attaching an article from Colorado State University on mulch types and what purposes they serve. I'm also attaching a good article on mulch from Oklahoma extension that talks about water penetration. This year, with watering restrictions coming to most of the Front Range you will want to balance the amount of water entering the soil with the most coverage to preserve it.
https://extension.colostate.edu/resource/mulching/
Mulching woody ornamentals with organic materials | OSU Extension Service
If the areas you're mulching are trees, shrubs or perennial beds, gorilla hair mulch would be okay, as are other options. Since you have pop-up sprinklers, the depth of the mulch is a concern since gorilla mulch does eventually form a mat which will hinder water from penetrating. This mulch is recommended for slopes and high-wind areas, since it stays in place. To get more penetration to the soil, use a more coarse mulch (bigger pieces) that don't form mats and allow better soil penetration.
You may want to consider grass clippings or leaves which are not as resistant to water, or less depth of whatever wood mulch you prefer.
Also, native perennials prefer small-sized gravel and rock, so that native flower and shrub stems don't rot from too much water.
I'm attaching an article from Colorado State University on mulch types and what purposes they serve. I'm also attaching a good article on mulch from Oklahoma extension that talks about water penetration. This year, with watering restrictions coming to most of the Front Range you will want to balance the amount of water entering the soil with the most coverage to preserve it.
https://extension.colostate.edu/resource/mulching/
Mulching woody ornamentals with organic materials | OSU Extension Service
