Cannabis cultivation is a new and rapidly expanding industry. Smart agriculture and precision growing techniques promise to increase cannabis yields, consistency, and cost-effectiveness. This article outlines why smart sensors are critical to automated, precision control in cannabis farming.

Using Smart Sensors to Optimize Yields in Cannabis Farming


In October 2018, Canada became the first G7 nation to legalize recreational cannabis use, joining 10 US states. Growing cannabis for medicinal purposes has also recently become legal in several countries including Australia, Denmark, Finland, Germany, the UK, and 33 US states.

Cannabis and cannabis oils claim a range of recreational, holistic, and pharmaceutical benefits including relaxation, pain relief, and treatment of a range of conditions including mental illnesses, cancer, epilepsy, and multiple sclerosis. As a result of varying degrees of legalization, the cannabis market has expanded rapidly over the past decade, along with regulation which has been designed to promote consistency among the products.

Cannabis cultivation is not yet fully optimized

The cannabis industry is still very young. Industrial cannabis growing practices are not yet fully developed, and as a result, many cannabis growers do not make full, efficient use of their land and resources to produce consistent, high-quality cannabis crops. While some cannabis growers utilize traditional outdoor growing practices, growing cannabis indoors provides year-round harvests, higher yields, and more security for growers. On top of this, research and commercial demand are providing an influx of reliable information based on specific strains of cannabis to be produced, making it imperative that their cultivation is accurate.

Recreational and medicinal cannabis products must contain a consistent amount of their active ingredients, to ensure sufficient levels of efficacy, patient safety, and customer satisfaction. It is particularly important to control the levels of tetrahydrocannabinol (THC), the psychoactive agent in cannabis; cannabidiol (CBD), which has been associated with some of the medicinal properties of cannabis, and terpenes such as myrcene, caryophyllene, humulene and others, which play an important role in a cannabis strain’s taste and smell as well as interacting to enhance or mellow the activities of THC and CBD.

Achieving consistent levels of active ingredients in plants requires exact growing conditions; for a reliable cannabis product, growers need a precise and consistent cultivation method, combined with efficient processes for monitoring and optimizing the characteristics of their cannabis plants including active ingredient levels.

Precision farming of cannabis can increase consistency and yields

Precision agriculture often involves specifically controlling light, nutrients, water, humidity, and air quality for stable crop growth. Cannabis growers are beginning to exploit research into precision farming to optimize their indoor and outdoor growing environments to improve efficiency while reducing costs.

The spectrum of light and its intensity are particularly important considerations for growing crops indoors. For cannabis growing, different lighting conditions can be used to optimize crop weight, density, cosmetic appeal, fragrance, terpene profiles, THC levels, and CBD levels.

For example, in the vegetative stage, an abundance of blue light can ensure healthy leaves, while during the flowering stage red light may be used to increase bud size. This has to be balanced with the need for a broad spectrum of light to promote a full profile of terpenes developing. Research has also found that the optimum temperature, humidity, CO2 levels, and plant nutrition parameters also vary according to the growth stage.

Traditionally, changing conditions for each cannabis growth stage has involved moving plants from one room to another after certain time periods or when changes in growth stages are visually observed. This is no longer necessary, with smart sensors and internet-enabled devices that allow farmers to automatically and remotely adjust environmental conditions, based on live analysis of growing conditions and the characteristics of their cannabis plants.

Spectroscopy enables live, online analysis of cannabis characteristics and growth conditions

Active ingredient levels and other properties of cannabis products are heavily influenced by growing conditions and as a result, must be measured during research and development, and routine quality control processes.

Monitoring the concentrations THC, CBD, and terpenes in cannabis plants can be particularly challenging. Traditionally, active ingredient analysis involved grinding a cannabis sample into a powder followed a lengthy extraction process, and chemical analysis using high-performance liquid chromatography (HPLC).

Although HPLC provides highly accurate results, it is a destructive method of analysis, so it is not a good candidate for online analysis of cannabis plants as they grow. What’s more, HPLC analysis only provides a measure of the active ingredients present in the particular sample measured; it does not provide information about an entire plant or batch of plants and can fail to detect heterogeneous growth. Furthermore, sample preparation, HPLC analysis, and interpretation require specialized personnel who are trained in chemical analysis.

Spectroscopic analysis provides the ideal alternative to traditional methods of cannabis characterization. Spectroscopy is a non-destructive technique that does not require any sample preparation. Optical spectrometers illuminate a target, such as a cannabis plant, with light (UV-Vis-NIR), and measure the absorption of each wavelength of light in the spectrum by the plant.

Chemical compounds absorb light at different wavelengths depending on the chemical bonds present in the compound, to produce a unique absorption spectrum. The absorption spectra of cannabis plants can be used to determine the concentrations of active ingredients and their distribution throughout the plant. In this way, spectroscopic sensors provide online analysis of the effects of growing conditions on THC, CBD, and terpene concentrations in cannabis plants with a percentage error of less than 1%.

Spectroscopic sensors can also be used to provide remote monitoring of crop weight, moisture, dry matter, nitrogen content, mineral content, and environmental conditions. Optical spectroscopy can also indicate the presence of weeds, pests, and diseases so that problems can be detected and dealt with efficiently. As a result, spectroscopic sensors enable smart systems to monitor plant growth and health, and adjust the growing conditions accordingly. Spectroscopic sensors provide live, non-destructive analysis of entire crops that is ideal for informing precision farming methods.

Remote monitoring and closed feedback loops in cannabis cultivation

Tec5 USA are experts in custom smart farming solutions, able to provide cannabis producers with a variety of technologies that integrate into a tailored solution, which is individual to each farm’s needs depending on the type of growing environment and level of automation needed.

Tec5 USA, provide the latest real-time, permanently-calibrated smart sensors that deliver full insight into plant health, potential yield, and cost analysis during the production process.

Smart sensors from Tec5 USA utilize optical spectrometers to monitor environmental conditions and plant status. Embedded spectroscopy, which combines distributed optical sensors with onboard, fast, reliable, and maintenance-free data processing, provides the ideal solution for precision, closed-loop cannabis cultivation.

Onboard processing removes the need for a PC interface to acquire and evaluate spectral data by communicating remotely with monitoring and process management tools to inform automated decision-making, resulting in increased consistency and efficiency at reduced costs.

Embedded spectroscopy can improve and automate many areas of cannabis production, and Tec5 optical spectrometers combined with the TecSaaS embedded controller provides the ideal system for use in automated cannabis cultivation systems.