Blooming cannabis market to drive demand for fertilizer minerals

By IM Staff
Published: Friday, 30 August 2019

Commercial cultivation of cannabis for medical uses is on the rise, with the sulfur, phosphate and potash sectors likely to benefit. But there are fears that the junior mining sector is suffering from a draining of potential investment.

Burgeoning growth in global cannabis cultivation for medicinal and recreational use is likely to boost consumption of certain fertilizer minerals, according to experts.

Mexico, Luxembourg, Canada and the majority of states in the United States (33, plus the District of Columbia), now permit the medical use of cannabis, and in November 2018 the UK amended its rules on prescribing medicinal cannabis in some circumstances.

Crop scientists see these developments as an opportunity for nutrient suppliers, once it becomes clear what inputs commercial cannabis crops require to boost yields.

"Research is comparatively scant on this topic," according to James Syrett, a lecturer in commercial crop production at Writtle University College in the UK. "Until recently, the crop has been considered too controversial and [too much if a] high-security risk to be worth conducting experiments into its fertilizer requirements."

Medical cannabis is usually grown hydroponically - without soil, using mineral nutrient solutions in a water solvent - so the full fertilizer requirement has to be met by the grower.

"The use of the appropriate nutritional measures - including organic fertilizers, supplements and biostimulants - is… a vital aspect of medicinal plant production, including medical cannabis," according to Nirit Bernstein, a researcher at the Agricultural Research Organization of Israel and lead author of a recent study into the effects of different nutrients on cannabis cultivation.

In recent crop trials, in addition to nitrogen, cannabis growers applied 45kg per hectare (ha) of phosphorus, 65kg per ha of potassium and 15kg per ha of sulfur, Syrett said.

"The sulfur requirement is notable, being slightly higher than [for the cultivation of] wheat. Mined sulfur fertilizers are becoming more important while sulfur pollution from cars and power stations, which used to provide some of the crop’s needs, decreases," he added.

Trials indicate that a high phosphorus content, from application of phosphate-based fertilizers, promotes the formation of tetrahydrocannabinol, or THC – the active compound used for treating conditions such as epilepsy.

Some of the world’s largest fertilizer mineral companies are understood to be watching developments in the cannabis industry closely, with some commissioning their own studies into the crop’s nutrient needs.

Most have refrained from naming cannabis as a potential demand driver, although Australian fertilizer producer Fertoz has highlighted the crop’s potential to boost nutrient consumption.

But the expansion of the industry is proving to be bad news for other parts of the mining sector. According to one financial adviser in London: "Cannabis company stocks are sucking the money out of the junior mining space."