Is weed vegan? Not so much. From cow blood to bat poop, growing cannabis can involve a lot of animals

Getty (Photographer: Chris Roussakis/Bloomberg)

When considering a vegan lifestyle, many look at their food and perhaps their clothing materials. But what about organically grown, Clean Green Certified® weed? 

Many organic agricultural products applied to add primary and secondary nutrients into soil are derived from or made by animals. Fish protein hydrolysate (FPH), blood meal, bone meal, and excrement are often added to soil or fed to plants in compost tea to promote root growth and terpene production. 

Before the meat packing industry, these nutrients were once natural byproducts on family farms or readily available from a neighbor’s ranch. But that symbiotic relationship has shifted into one of mass production and, in turn, a cycle of what some would call animal cruelty. Many animal ingredients used in cultivation products come from slaughterhouses and fish mills that don’t align with the cruelty-free ethics of veganism. 

Let’s learn a little more about some animal ingredients commonly used in cannabis cultivation.

Non-Vegan Cannabis Nutrients

Fish protein hydrolysate (FPH) 

FPH is made from fish meat that ferments into highly bioavailable amino acids. In cannabis cultivation, it’s often used as a non-burning source of nitrogen that feeds the microbial population of the soil. The raw fish and fish byproducts used in agricultural grade FPH are sourced from fish farms and hatcheries. 

Blood Meal and Bone Meal

The dried powder of purified cow’s blood is commonly used as an organic nitrogen soil supplement. Its counterpart, bone meal, is made from steamed and ground animal bones. Bone meal supplies phosphorus to the soil, so these products aren’t interchangeable, but they are both byproducts of slaughterhouses.

Worm Castings and Guano

Excrement is an age-old fertilizer, and there’s room to wiggle as to whether worm castings or bat guano would make a cannabis plant non-vegan. We won’t delve into the works of Peter Singer, but it is worth taking stock of how they harvest excrement before deciding. Worm castings are difficult to harvest without hurting the worm, and as for bat guano, it is often harvested from their caves at night while the bats are out hunting. Some farmers argue that animal droppings collected from free-living animals fit within the plant-based growing methods called veganics. Since veganics isn’t a defined term, the use of excrement seems to vary from farmer to farmer. 

So, is any cannabis vegan-friendly?

A pot-loving vegan may feel defeated, but vegans, don’t despair! There are plant-based soil additives like neem oil, alfalfa meal, and gypsum. 

If there are alternate options to animal blood and bones in compost tea why don’t more farmers switch over to vegan cultivation methods? Participants in a 2021 study described the challenges with vegan farming, the most common being sourcing veganic products in a market of unclear or inadequate product labeling. Farmers also cited a lack of access to information about vegan farming. These challenges make veganic farming more complex than organic or synthetic farming. But there are resources like the Vegan Agriculture Network and the Vegan Organic Network that assist farmers interested in veganics.

So, is weed vegan? Strangely enough, not for the most part. But don’t despair. There are many cannabis farms using veganic growing methods across the country, and as cannabis becomes legalized in more states each year, the amount of vegan-friendly cannabis in the world is sure to grow.

Cara Wietstock is Senior Content Producer of and has been working in the cannabis space since 2011. She has covered the cannabis business beat for Ganjapreneur and The Spokesman Review. You can find her living in Bellingham, Washington with her husband, son, and a small zoo of pets.

Cara Wietstock Associate Editor