You may have heard of hemp and thought it was another name for marijuana. I know I did. On the contrary, hemp and marijuana are different plants. Hemp has dozens of applications in many different industries, and using hemp over conventional materials is better for the environment. So let’s take a look at some of the uses for hemp to see how this one plant could help our planet.
What Is Hemp?
First of all, what is hemp and how is it related to marijuana? According to Leafly.com, “[b]oth hemp and marijuana come from the same cannabis species, but are genetically distinct and are further distinguished by use, chemical makeup, and cultivation methods.” Hemp does have some THC (what gives you a high), but it is less than 0.3%, which isn’t enough to affect humans.
Hemp and Sustainability
What makes hemp so sustainable? Hemp grows very quickly (just a few months) and can be harvested every year in perpetuity. It is a hardy, frost-tolerant plant that can grow on every continent except Antarctica.
The plants grow up to 15 feet tall and grow close together, which prevents weeds from sprouting up. This means there is no need for herbicides. They are also resistant to pests. No pesticides needed either.
While most plants steal much of the nutrients in the soil and degrade it over time, hemp returns 60-70% back to the soil after harvest and prevents erosion. Because of this, many farmers use it as a rotation crop to help maintain good soil.
The fast growth is due to the large amounts of CO2 hemp plants absorb from the air. Their efficiency actually makes hemp a carbon negative plant. Its quick growth and resistance to pests and disease allow hemp to produce more biomass than any other plant which can be put to good use.
History Of Hemp
With all of these great qualities of hemp (and we haven’t even gotten to the material qualities), why don’t we all grow it? Surprisingly, we used to. A lot. There are records of hemp being used in Asia all the way back to 8000 BC. In America, many of the founding fathers like George Washington grew hemp, and up until 1937, hemp was a major crop in America.
As a result of the movie “Reefer Madness” spreading fear of cannabis in the US, the Marijuana Tax Act passed in 1937, which regulated both cultivation and sale of cannabis, including non-psychoactive hemp.
Then the Controlled Substances Act of 1970 classified all cannabis forms as Schedule I drugs so hemp became illegal to grow or possess. The War on Drugs and fear of cannabis destroyed the hemp industry in the US and other countries around the globe, although some like the Soviet Union still produced large amounts (3,000 km² in 1970).
Commercial hemp production resumed in Canada, Germany, and the UK in the 1990s, requiring special licenses that certify the hemp grown will contain less than 0.05% THC. China is the highest producer of hemp currently, followed by France, Austria, and Chile. Hemp grown in the EU can even be certified as organic.
In the US, however, hemp production remained very restricted, although some legislation in recent years has opened the doors. The 2014 Farm Bill allowed states to grow hemp for research and development purposes. The Hemp Industries Association (HIA) estimated that $620 million worth of hemp products were sold in the US in 2014.
In 2015, the Industrial Hemp Farming Act was introduced in the House. This act would have amended the Controlled Substances Act such that it would be legal to grow and possess industrial hemp so long as it is in accordance with state laws, but it was never brought to a vote.
Luckily, the 2018 Farm Bill created the USDA Hemp Production Program, authorized hemp production in the US, and removed hemp and hemp seeds from the DEA’s list of controlled substances. This opens up so many possibilities for this amazing plant.
Uses For Hemp
So now that you’ve learned all about hemp its history, let’s talk about its many uses. As discussed, hemp has been used for thousands of years for food, textiles, paper, and other products. With today’s technologies, we can process hemp into replacements for fossil fuels and plastics too.
Most products come from the double layer stalk. The outer layer with long rope-like fibers is used for textiles, while the inner woody layer is used for other purposes like fuel or construction materials.
Textiles And Clothing
Hemp fabric comes from the outer layer of the stalk. These long strands are separated from the bark during a process called “retting“. The strands are then gathered and spun into a thread to be woven into fabric. Many phases of production can be done mechanically without the aid of chemicals, although some companies use chemical processes instead to save time and money at the expense of the environment.
Benefits Of Hemp Textiles
Hemp is the strongest natural fiber. This strength and flexibility made it the best rope-making material. It has also been used for twine, netting, boat sails, and ship rigging. But there are even more uses for hemp fibers.
It is common to blend hemp fibers with another material, usually cotton or silk. Combining with silk creates a fabric that is softer than hemp but still very strong and durable.
Hemp Versus Cotton
Compared to cotton, hemp is the clear winner. It uses half the water needed to grow the same amount of cotton and, remember, none of the herbicides and pesticides. On the same patch of land, hemp will produce 250% more fiber.
Hemp softer than cotton but will last twice as long. Unlike other fabrics that wear out with use, hemp keeps its strength but gets even softer with use. Its porous nature also gives it a better ability to retain its dyed color than cotton and other fabrics.
Hemp has been used to make paper for thousands of years, and it’s actually much better than paper made from trees. First of all, hemp produces two to four times as much paper as the same area of trees would. This makes hemp more economical and environmentally friendly than trees. Switching to hemp paper products will help prevent deforestation and habitat loss caused by the logging industry.
Hemp paper does not degrade or discolor like tree paper, allowing it to last for hundreds of years. Additionally, it can be recycled more times than tree paper products and requires less chemicals to process.
The hemp plant has many uses for human nutrition. Leaves can either be eaten as a salad or pressed into a healthy green juice. Hempseeds contain lots of proteins, minerals, and fiber. They are also high in Vitamin A, various B vitamins, potassium, phosphorus, iron, copper, and magnesium.
Hemp is actually the only plant that contains the important fatty acids and all nine of the amino acids humans cannot produce themselves. Their fatty acid content makes them a great alternative to fish oil supplements. The production of those supplements contribute to overfishing and ocean pollution.
You can eat hempseeds on their own, or they can be crushed into a flour for baking or a cooking oil. As with many types of nuts, you can make hemp milk from the seeds, but hemp can also be used to make beers, wines, and other alcoholic beverages.
Hemp is also good when used outside the body. Hemp oil is non-comedogenic so it doesn’t clog up pores like ingredients used in many lotions. It contains beneficial oils and is soothing to the skin, which is why it is now being added to many skin, hair, and cosmetic products. Hemp contains EFA which moisturizes and heals dry, cracked skin and reduces dandruff caused by dry scalp.
Humans aren’t the only ones who can take advantage of eating hemp. The proteins and other nutrients in hemp make it great for pet food and dietary supplements. Hemp can be a substitute for corn-based animal feed, which is worse for both the environment and the animal.
The inner layer of the hemp stalk can also be used in animal care. Hemp bedding is available for small pets like guinea pigs, rats, and hamsters, and hemp can substitute in for cat litter.
As with corn, hemp can be turned into an ethanol biofuel to replace diesel. This hemp fuel is more renewable than fossil fuels and results in less greenhouse gas emissions. Before electricity, hemp oil was used to fuel lamps and lanterns for centuries.
Hemp biofuel meets the ATSM D6751 and EN 14214 standards for biodiesel quality and is better than other plant-based fuels. Hemp produces 800 liters of fuel per hectare, which outperforms other plants. It even outperforms diesel in every category except oxidation stability, although that can be remedied by the addition of antioxidants.
If you’re curious about the production process, here’s a quick look. It’s called cellulolysis and has six stages as outlined by the Hemp Gazette:
- “Pre-treatment to make the cellulose content in hemp suitable for hydrolysis.
- Breaking down the molecules into sugars using an enzyme that converts cellulose into glucose (cellulase).
- Separation of sugar materials from the lignin.
- Fermentation of the sugar solution.
- Distillation to extract the ethanol.
- The use of molecular sieves to increase ethanol concentration.”
Fossil fuels power our cars and machines, but we also use them to make plastics. And hemp can help with that too! Hemp-based bioplastics are non-toxic alternatives to plastic that are usually biodegradable. Remember though that bioplastics are not 100% natural and still contain some conventional plastic that will never fully break down.
These bioplastics are lighter and 3.5 times stronger than petroleum-based polypropylene. They also have high UV and thermal stability. Since the plants are renewable, we don’t run the risk of running out of it like we do with fossil fuels.
Hemp plastics have been used for many different items including shower curtains, DVD cases, packaging, and even car bodies. Speaking to that last point, Henry Ford himself designed a car body using a hemp bioplastic back in 1941, but it never went into mass production.
The last main category of uses for hemp is construction materials. Construction is a resource-intensive industry, using “about 40% of the world’s global energy, 25% of the global water, and 40% of the global resources“. Substituting in hemp products can help reduce those figures.
Wood And Other Products
Hemp materials can replace wood in many applications. Hemp fiberboard is both stronger and lighter than wood. Hemp-based products can also replace wood for walls, shingles, and paneling. There are hemp-based paints and varnishes that are non-toxic and even pipes made from hemp.
The most interesting building material using hemp is called hempcrete. The inner layer of the stalk is mixed with a lime- or clay-based binder to create a bio-composite concrete material. The result is a great insulating material that weighs seven or eight times less than concrete.
Uses For Hempcrete
Hempcrete is not normally used as a structural element, although ten story buildings and bridges using hempcrete have been built in Europe. Instead, it is commonly used as building insulation, plasters, and floor slabs. It can, however, be used in some structural and load-bearing applications.
Benefits Of Hempcrete
Using hempcrete is great for the environment. Hempcrete sequesters lots of carbon, keeping it out of the atmosphere. For example, an “un-rendered 30 cm thick hemp concrete wall enables a storage of 36.08 kg of CO2 per m²“. The use of lime over cement saves 80% of the released CO2, and using clay binders instead of lime will increase those savings even more.
Since hempcrete is a great insulator, the building will require less energy to maintain a given temperature. This will reduce energy costs and greenhouse gas emissions. Furthermore, hempcrete is easier to work with and less brittle than conventional concrete.
Here is a list of even more benefits of hempcrete from the National Hemp Association:
- No off gassing
- No solvents
- Mold resistance
- High vapor permeability
- Humidity control
- Carbon sequestration
- Fire and pest resistance
- Passive self-regulation of temperature and humidity
- GREAT insulator”
Other Uses For Hemp
Finally, I wanted to just add a quick sections on even more uses for hemp that weren’t covered in the categories above.
- Soil contamination cleanup
That last use deserves a bit more detail. After the Chernobyl nuclear disaster, industrial hemp fields planted at the site helped decontaminate the soil. The plants helped to clean areas contaminated with fly ash, sewage, and heavy metals, proving it has huge potential for fixing our environment.
As you can see, the uses for hemp are nearly endless. This one plant can replace many ingredients and products that are harmful to ourselves and our planet. It can clean up and add nutrients to soil, and it grows so much so quickly that it is a nearly renewable resource capable for use in dozens of applications.
I believe expanding production and use of hemp products along with algae products could turn the tide of climate change and environmental destruction. Want to learn more about what algae has to offer? Head over to my other post!