Sustainable Sourcing Guide

Overview: There are many aspects to sourcing, including flavor, cost, labor intensity, environmental impact, availability, etc. This guide will focus on decoding the considerations involved with environmental impact, which already is exceedingly complex, albeit just a part of the overall decision. No restaurant could succeed solely by focusing on minimizing environmental impact, so this information is meant to inform decisions, not dictate menu design. Note: This guide will represent a Northern Californian point of view, but the same principles can be applied to other regions.

Carbon Footprint = The Perennial's measure of impact

Ingredients and principles will be primarily evaluated based on carbon footprint (CO2 equivalent AKA CO2e), since that is the area that is the least understood and since that touches on water and labor. Let us acknowledge that water and labor are also important, though they will not be the focus here.

Conventional vs. Organic vs. ...

There is a wealth of information about the carbon footprint of conventional ingredients. This is the carbon footprint of 60 common ingredients. Everything will be listed as CO2e and also as gallons of gasoline burned, for context.

The term "organic" has been used in popular culture in the U.S. for about 40 years and now accounts for about 5% of the food in this country. The organic certification is costly and takes several years and includes a range of soil-building farming practices of varying impacts on the planet. That is, farms that plow frequently and spray approved chemicals can be certified organic right alongside other farms practicing regenerative or biodynamic or other "beyond organic" methods. In other words, "organic" is not a perfect measure.

Research by The Rodale Institute suggests that organically produce row-crops typically have 40% lower carbon footprint than conventional, but overall, there is very little information about the carbon footprint of organic produce because of the wide variation within the category.

"Regenerative agriculture"

Regenerative is a relatively new emerging consumer category that is loosely defined and enforced. It applies to soil-building farming practices. You could envision this as similar to planting trees, but instead, repopulating soil with microbiology, roots and fungus. A simple, but effective way to conceptualize this is through the metric Soil Organic Matter (SOM%). This is truly the amount of organic matter in the soil and typically varies from 0.5% to about 10%. Generally speaking, a farm with SOM% above 5% is good, but it varies from region to region and soil type to soil type and it’s actually very complicated, so it’s not useful to place too, too much emphasis on the number. For more information visit

This category includes certain certified organic farms as well as farms that are not certified organic, and so it would not preculde a "beyond organic" farm that chose not to pursue certification, or a large scale conservation agriculture farm that happened to use an herbicide one year to save a harvest, or might microdose-adding a small squirt with each seed but not spraying an entire field with an approved herbicide. The most important practices include:

  • not plowing or infrequent plowing
  • cover cropping
  • crop rotation/polyculture
  • Fertilization through compost or grazing instead of chemicals
  • minimal or no synthetic herbicide or pesticide.**

The integration of perennial plants and hedgerows can provide added soil benefits, but is probably in a lower tier of importance.

The overall principle is that healthy soil is biologically active. Flavor and nutrient density in plants results from the bioavailability of minerals like copper, selenium, vitamins, calcium, etc. As such, the presence of the minerals in the soil is just one factor in the quality of the product. Since most soil possesses trace amounts already, the biology that transfers what is in the soil into the plant is often the biggest variable in produce quality and changes more across farming styles. Despite very high levels of fertilizer use, most vegetables grown conventionally have seen alarming, gradual declines of vitamins and minerals over the last 40 years.

From the perspective of water use, more biology equals more water retention—think a loaf of bread as opposed to a bucket of dirt. Each additional 1% of SOM% can hold 20,000 gallons of water per acre.

From the perspective of environmental impact, the carbon held in the soil can be massive. The top 12 inches of one acre of soil is 40 million pounds, so each percent of organic matter in an acre represents 400,000 lbs of organic matter, which is in turn 50-58% carbon. So if a farm increased its SOM% 1% it would be kind of equivalent to not burning over 100,000 gallons of gasoline, or 25,000 saplings growing for 10 years. What’s complicated is, let’s say a farm had SOM% of 8% and the baseline for the specific micro-region was 7%. How much environmental benefit should be assigned for maintaining this land above the regional baseline? Also, the SOM is transient as opposed to unburned fossil fuels, so the benefit is not locked in for the long term. Also of note is that philosophically and socioeconomically, this creates the greatest opportunity for soil restoration among the farms with the most degraded soil. The Healthy Soil Guide recognizes both high levels of SOM% relative to the regional baseline, as well as rate of SOM% increase.

In most cases, regenerative agriculture is more labor intensive, but creates higher yields per acre and does not expose workers to chemicals. Anecdotally, some farms practicing regenerative agriculture achieve sush high levels of productivity that they are able to harvest 5-8 times per year, providing year round employment for their staff.

Plant Forward

The Perennial celebrates natural diversity, offering meat, grains, fruits and vegetables produced with farming practices that improve soil health. While we believe sustainably raised meat is part of a positive environmental system, we also advocate for a consumption pattern that mirrors natural systems and market availability.


Meat represents the ingredient with the highest environmental impact—either good or bad and so deserves the most analysis.

One of the most interesting developments in the past 5-10 years in terms of food and the environment is the new understanding that animals and the fertility they can provide to soil represents a massive climate solution. February 2018 marks the publication of the first peer-reviewed study showing the carbon footprint of beef raised under adaptive multi-paddock grazing to be negative. (AMP Grazing: -6.62 kg CO2e per kg of cow compared to the pre-existing estimate of +9.65 kg CO2e per kg of cow). The work of the Marin Carbon Project incorporates both managing the grazing of the cattle, as well as applying compost to the field to jumpstart the soil restoration. The measured annual benefit from 350 acres managed this way is equivalent to not burning 250,000 gallons of gas every year.

For reference, bigger picture, there are fewer lbs of livestock in the US today, despite our high level of beef consumption, than the amount of bison previously. Each cow produces 50-70 lbs of manure per day. The manure from beef raised with antibiotics cannot fertilize fields ad is often held in lagoons where it continues to off-gas methane. Cattle raised on feedlots eat a diet that is resource and land intensive, which compounds the environmental impact if considering the opportunity cost of each acre of land. And then, since cattle eat an unnatural diet and are often crowded, feedlots create very negative animal welfare.

There is very little carbon footprint data on the extent of the environmental benefits of grass-fed beef and pastured poultry and pork, etc. because most studies do not assign significant soil benefits to these practices. And for example, if the transition of a 100% grass-fed ranch to adaptive multi-paddock grazing changes the carbon footprint from +9.65 to -6.62, then it becomes impossible to make assumptions about the specific merits of a given ranch.

Our goal is to find the ranches with high SOM%, but overall to support pastured animal protein as a foundational mode that easily transitions into carbon ranching. We can think about this from a common sense perspective: cows and sheep may have a higher carbon footprint because of methane flatulence, but also have the most potential for climate benefit because they are eating only grass. Pastured pigs and poultry are utilizing minimal resources and contributing their manure to the pasture. While the actual levels of carbon sequestration may not be as high as the optimal modes of beef production, we believe they are part of a sustainable food system.

The Perennial started this list on wikipedia and is working on a movement among ranches to recognize soil building practices.

Specifically, The Perennial sources large primal cuts and/or whole beef and lamb from Stemple Creek Ranch, which is 100% grass-fed and has adopted a carbon ranching protocol on 350 acres. We insist on meat being pastured and ask all of our pork and poultry suppliers to provide soil organic matter data (whether or not they provide it is another story…). This is important because, for example a 50 hog operation provides $4000 worth of fertilizer to a field each year. We’ve supported Full-Tilt Farms, Emmer & Co, Klingeman Ranch and Devils Gulch Ranch.


We Source seafood from TwoXSea and Water2Table. They do an excellent job of providing quality products that are grown sustainably like McFarland Springs Trout, which has great flavor on a vegan diet and applies fertilizer to surrounding meadows, monitoring to prevent runoff.

Staple crops

Staple crops comprise the majority of calories eaten in the world and most are annual, including corn, soy and wheat. in many cases, the annual plants occupy growing areas that were previously comprised of perennial polycultures, and their presence has resulted in the gradual release of soil organic matter from those fields. Ideally mankind would source calories from land/practices that improve soil. One such crop is kernza, a perennial grain that was just developed after ~15 years of natural breeding and creates enough soil benefit that it can be considered carbon neutral. Many organizations are working on Perennial Wheat, but it’s not likely to be in the marketplace for 10-20 years.

There is a lot of information on perennial staple crops here.

Many perennial plants are delicious and well known like nuts, avocados, etc. but depending on the grower and the area, some of those plants can be very water intensive. The best case scenario is if the trees are part of a polyculture and if the orchard reports a high level of SOM%.


As seen by the carbon footprints chart, vegetables have a relatively low carbon footprint. Given the prevailing disconnect between a chef or consumer's ability to understand or measure aspects of farming, the best approach is to just make choices based on flavor, seasonality and locality. That said, we don't believe it’s useful to draw very specific boundaries because something grown 200 miles away that got to 30 miles away as a passenger along with other cargo is going to have a lower carbon footprint from travel than something deliberately driven 50 miles, etc. Whenever possible, we ask for a farm's SOM% to try and bridge the disconnect and to start a meaningful conversation.

Overall, as alluded to earlier, there is more impact across farming practices, than across ingredients. Organic is better than Conventional and high SOM% is a great indicator of environmental benefits. Among less conscientious farmers, growing perennials might tend to involve less soil disturbance and/or might be more prone to be part of a crop rotation, but would not intrinsically have major environmental advantages unless they were part of perennial rotations. Here are some common perennial vegetables:

  • raspberries, blueberries and other berry bushes
  • asparagus
  • rhubarb
  • horseradish
  • globe artichokes
  • lovage
  • watercress
  • sorrel
  • sunchoke
  • ramps
  • scarlet runner beans
  • gai lan
  • dandelion
  • nettle
  • water chestnut
  • water spinach
  • chayote
  • cassava
  • nopale
  • pigeon pea

unusual perennials to explore—might provide ecosystem benefits as part of a crop rotation:

  • daylilies
  • ground nut
  • good king henry
  • bunching onions
  • ostrich fern
  • sea kale
  • sea beets

Some SOM% data regarding specific farms that has been compiled (reminder to not place too much weight in comparing the numbers--all of these SOM% are probably radically higher than the certified organic produce at Whole Foods or what not):

  • Alemany Farm: ~10%
  • Jackson Family Vineyards: ~10%
  • Singing Frogs Farm: 6.5% - 9.0%
  • Pie Ranch: 3.5% - 5.3%
  • Markegard Grass Fed: 7.1%
  • Tomkat Ranch: 7.9%
  • Root Down Farms: Soil Carbon: 2.8% (= ~5.6% SOM%?)

There is also extremely thorough soil carbon data here, but the entries are not necessarily formatted for consumers or chefs (you kind of have to cross-reference to figure out what data point is what farm or ranch).

Food Waste

Food Waste is a major problem and an obvious one. Food accounts for about half of all greenhouse gas emissions, and we waste about 40% of all food. But even beyond the lost usage, the actual wasting part makes things even worse.

In areas that don’t compost, food waste has a significant carbon footprint. Each 10 pounds of food waste releases methane in landfill, creating almost 9 KG CO2e, or about the impact of burning a gallon of gasoline. This does not take into account the growing and production of the food, just the impact once it goes into landfill. Sorting food waste to keep it out of the trash and into the compost is an import environmental act and every bit as important as recycling. It also underscores the importance of composting. If you are in a region that offers composting, it’s an important choice to pay for that service and utilize it. That food waste will become organic matter in your region’s soil. Each gallon of compost that is part of carbon ranching program provides as much environmental benefit as not burning a gallon of gas—it can have that much of an impact.

Also, as such, anything that would have actually been thrown away can be seen as a carbon negative ingredient to utilize.

Companies/growing styles to support

  • Straus Family Creamery - Albert and the team have a thorough commitment to sustainability ranging from methane digesters and manure-powered vehicles to 1 of the 9 dairies operating under a carbon farming protocol. Perhaps soon to be more.
  • Aquaponics - food grown in cities using natural fertilizer - low food miles and leaves soil available for more regenerative farming.
  • Urban farming and suburban farming that utilizes compost from the city (aka not synthetic fertilizer based urban farming)
  • Lotus Foods - Fair Trade company championing Improved Rice Cultivation for significant emissions reduction and water conservation
  • Timeless Seeds - Crop Rotation as a source of nitrogen; cooperative among “renegade” Montana farmers breaking from the Industrial Ag treadmill.
  • Greenwave - Seaweed Farming as a scalable climate solution

Second Tier

  • Brackish Greens - grown in high salinity soil, food produced in otherwise unproductive land
  • Tehapachi Grain Project - Heirloom grains with various benefits (local/native/resilient)
  • Insect protein