27 Jun Part 4: Is Living Mulch Better than Dead Mulch?

What is living mulch? you might ask. Let’s first address what mulch is. In the ornamental horticulture world, mulch is something that covers the ground and:

• Visually anchors the landscape to the site
• Shades and insulates the soil from temperature extremes and fluctuations
• Prevents competition from weeds
• Helps seal in moisture by reducing evaporation

Typically, mulch is either a wood-based material, or gravel. Both have advantages and disadvantages.

Living mulch, as the name implies, is living! It’s plants planted closely enough that they provide all the above services. This dense planting that comprises living mulch can be plants of many heights, as you can see in the photo. The goal is for the plants to touch edges or overlap a bit by the time they reach maturity. Low spreading shrubs like Gro Low sumac or manzanita fit the bill, as does creeping thyme and Turkish veronica, and all the sizes in between. Or, simply planting all your shrubs and perennials closely enough to achieve this mulch effect works just as well. Personally, I like varying the height to create a more dynamic, interesting landscape, as shown in the photo.

Living mulch has many benefits:

• Firewise. The moisture in the plants make for a much less flammable situation than a woody mulch.
• Regenerative. Plants grow, seed, and fill in
• Creates habitat. Pollinators and other characters in the story of our local ecology find what they need to survive more easily when there is more biomass and greater biodiversity, which is increasingly important as habitat in nature dwindles. Living mulch provides a much richer resource for them than wood or gravel mulch.
• Beauty & lushness. Filling in the “spaces” in our landscapes with more plants – groundcovers or otherwise – greens up our spaces and creates more of a feeling of being “in the garden” than being in a brown, sparsely planted landscape dominated by non-living mulch

How does living mulch fit into this year’s Columbine newsletter theme of sustainable landscaping? Glad you asked. When sustainability is defined as nature in balance, and maintaining integrity into the future, it becomes apparent how the above offerings of living mulch deliver just that.
It’s also worth noting that living mulch contributes to making us more sustainable, happy, and resilient as a (human) species. By inviting the wonder of beauty of nature’s critters into our outdoor spaces where we spend time, we enjoy the benefits of biophilia. It is scientifically proven that we increase our well being, focus, creativity, and so many good things by spending more time in nature, and where better to do it than at home?

To the Glory of the Garden,

Eva Montane,

Columbine Landscapes, President