June 7, 2026
Hi Reader,
Last weekend Purgula attended the Earthstock Regenerative Summit—an intimate sustainability festival held in the beautiful hills of Ojai, California. We went as curious observers, as we often do, looking for emerging ideas, innovative thinkers, and the kinds of conversations that don't yet show up in mainstream channels. We found all three—and then some.
Among the speakers was Michael Wittman of Blue Sky Biochar, a soil scientist, innovator, and self-described educator whose passion for what lies beneath our feet is contagious. His area of focus is biochar—a carbon-rich material produced from organic waste that has been used to restore depleted soils for thousands of years.
Though we consider ourselves avid gardeners, neither of us had ever heard of biochar.
That was the first surprise. The second was everything we learned next.
Biochar, it turns out, is not simply a soil amendment—though its ability to restore degraded, contaminated, and nutrient-depleted soil is remarkable enough on its own.
Biochar is a material with a surprising range of applications that extends from neutralizing toxic soil all the way to improving the insulation of the walls in your home.
It strengthens cement. It can be mixed into plaster. And in one of the more unexpected turns of an already surprising conversation, it acts as a natural Faraday cage—blocking electromagnetic waves in a way that has attracted serious attention from builders and architects focused on indoor environmental quality.
We also learned that awareness of biochar outside specialist circles remains surprisingly low. Despite centuries of precedent and decades of modern research, it is one of the best kept secrets in soil science and sustainable building. That is beginning to change—slowly, in the way that genuinely transformative ideas often do, working their way from the edges toward the mainstream one curious conversation at a time.
One comes to mind:
Have you ever thought of the soil beneath your home as either an asset or a liability?
Likely not, as most homeowners obsess over what's above the ground—finishes, fixtures, curb appeal, square footage. But the biological health of the soil their home sits on directly affects drainage, foundation stability, landscape performance, water costs, and even air quality.
Biochar reframes soil from something you manage reactively into something you invest in proactively.
This week's in-depth article is our attempt to bring the remarkable properties of biochar to you in full—what it is, what it can realistically do for your property and your projects, where to get it, and why we think it connects to one of the most important emerging trends in residential design and land stewardship: regenerative homes and living soil. It is a thread we will be revisiting for months to come.
Biochar invites a different question:
What if the ground itself were treated as one of your home's most valuable and improvable assets?
Biochar also marks the latest addition to our ongoing exploration of the materials redefining what homes are made of and how they perform—from Cork and Copper to Quartzite, Permeable Paving, and beyond. If you haven't explored our Materials archive yet, this is a good moment to do so. Biochar may be the most surprising example yet. Read on to find out why.
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