In this week’s episode of The Permaculture Vine Podcast, Graham Towerton from Permaculture Canada discussed a recent tree-planting project at a solar farm in Adrian, Michigan, and the broader concept of agrivoltaics—incorporating agriculture within solar farms.
The Tree Planting Project
Graham’s team recently completed a $325,000 contract to plant 1,122 Black Hills spruce trees around a solar farm. The project took six weeks and involved replacing trees that a previous contractor had planted, more than half of which died within the first year.
The trees are required by local ordinance to create a 150-foot buffer zone around the solar farm. They must be evergreens, planted at 10-foot intervals, and six feet tall at installation.
The team included Graham’s daughter Lily, Azura, farm manager Julia, and several other participants. The work involved removing dead trees, digging holes, planting new trees, removing cages and burlap, and mulching.
The Ordinance Issue
The local township ordinance requires that all vegetation inside the solar farm be kept under 12 inches in height year-round. This requirement was causing unintended problems.
Graham observed that monarch butterflies and other insects were abundant on the property when the clover and other plants were allowed to grow. After the required mowing, the insects disappeared because their food source was gone.
When Graham presented this observation at a township board meeting, board members were receptive to discussing changes to the ordinance. He plans to work with them to revise the rules to allow for deeper vegetation and more diverse plantings.
What Agrivoltaics Means
Agrivoltaics refers to incorporating agriculture into solar farms. The specific options depend on the design of the solar installation.
Graham’s neighbouring solar farm has panels mounted 5-6 feet off the ground on north-south rotating bars that track the sun from east to west. This design limits what can grow directly underneath.
Some other solar farm designs are more accommodating:
* Dutch solar farms mount panels 30-40 feet high, allowing tractors underneath
* Some newer panels are translucent, allowing light through for vegetation
* Circular tube designs that rotate while following the sun
Michigan State University has developed guidelines for grazing sheep in solar farms. Sheep don’t climb on panels like goats do, making them a better option for vegetation management.
Buffer Zone Opportunities
The solar farm has about 25 acres of buffer zones outside the fence that are currently just pasture. The company has told Graham they’re open to ideas for using this space.
Potential uses include:
* Community gardens
* Tree farms to grow seedlings
* Regenerative pasture with livestock grazing
* Perennial crops like raspberries and asparagus
* Wildflower meadows along stream beds
The solar company requires that any vegetation be planted no closer than 3X its maximum height from the nearest panel (to avoid shading). This only applies on the east and west sides of the arrays, not north and south.
Farm Land and Solar Development
The conversation touched on concerns about solar farms taking up agricultural land.
Graham noted that in Michigan, Indiana, and Ohio, farmland is disappearing under both urban sprawl and solar farms. The particular 160-acre section that became the solar farm next to his property sold for approximately $2.5 million before the solar development.
However, he pointed out that much US farmland isn’t producing food for human consumption:
* 97% of corn (100 million acres) is GMO and goes to animal feed and ethanol
* 96-97% of soybeans (100 million acres) are GMO, crushed for biodiesel oil and animal meal for livestock
* Wheat (80 million acres) is the main grain crop still grown for direct human consumption
The traditional Midwest farming model—where a family would grow diverse crops and raise animals on 80 acres—largely disappeared in the 1940s-50s, replaced by large-scale monoculture production.
Future Plans
The tree-planting project has opened doors for Graham’s team. The solar farm manager has invited them to bid on mowing 440 acres across multiple solar farms, and other solar companies in the region have expressed interest in working with them.
Graham plans to develop a proposal for Permaculture Canada to design and implement agricultural systems in the buffer zones, potentially including community gardens with public access and educational components.
Azure suggested creating an information centre at the solar farm where visitors could learn about how the panels work and what they produce, helping address misinformation about solar energy in the community.
The full podcast includes additional discussion about rural depopulation, distributed vs. centralized energy systems, and the team’s upcoming travels to Central America.
