THE IMPACT OF HEMP ON THE ENVIRONMENT
After asking, “Is hemp good for the environment?”, we learned that hemp is much more environmentally friendly than virtually all other major crops.
While it’s not perfect, the net effect of hemp on the environment seems to be almost 100% positive as long as it’s used in rotation. If used as a rotation crop, the benefits of growing hemp far outweigh the drawbacks.
Hemp is carbon negative, meaning it “sequesters” (or absorbs) more carbon during growth than is used to harvest, process and transport it (see reference 1). This is particularly true when it comes to the production of “hempcrete”, which is a good store of carbon. In contrast, one tonne of cement releases one tonne of carbon dioxide into the atmosphere (reference 2).
Hemp requires few pesticides and no herbicides, making it much easier to grow it in a sustainable or organic way. It enhances biodiversity by supporting many kinds of insect.(3)
It’s an excellent rotation crop, and is often used to suppress weeds and loosen soil before a farmer plants winter cereals.(4)
With its deep root system and general hardiness, it’s a useful tool in reclaiming poor or unused land. As it’s “phytoremediative”, it actually heals the soil by absorbing pollutants.(4)
- When grown as a textile, it uses less land and water than cotton.(5)
As with most commercial crops, the industrial cultivation of hemp depletes the soil of key fertilizing compounds such as nitrogen, phosphorus and potassium, and hemp needs deep, nutrient-dense soils.(6)
While better than many other crops, hemp does also require significant amounts of water.(3)
There is the risk of hemp becoming an invasive species in environmentally-sensitive zones because it is tough and competitive. Care is therefore needed to ensure protection of Australia and New Zealand’s unique habitats.(7)
- Finally, farmers are often tempted to have hemp monoculture because of its many versatile uses, so the government should encourage them to use it as a rotation crop.(7)