Cannabis has shown no signs of slowing down in the 25 years since California became the first state to legalize it for medical use. Though still in its infancy, the cannabis industry now supports more than 400,000 full-time jobs and is projected to add an estimated $100 billion to the US economy in 2022.
But at the end of the day, cannabis is an agricultural product that’s still federally illegal. That means there’s a whole lot riding on growers being able to cultivate it successfully - and that’s not the only thing on their minds. They must also achieve potency, track each plant from seed-to-sale to fulfill compliance, and deliver a consistent product experience to consumers time and time again. For an industry that is both heavily regulated and lacking in centralized systems and practices, profitability and scale won’t happen with gut instinct alone.
After decades of experience developing sensors and solutions for multiple sectors including food and agriculture, we created AROYA as a way to help growers improve their grams per square foot per year using an approach to plant management called crop steering.
This simple crop steering guide breaks down the basics for growers new to the process.
What Is Crop Steering?
To live plants need light, water, and a place to grow. When cultivating in an indoor or greenhouse setting, it’s the grower’s job to create a nurturing environment for the plants that is as close to nature as possible. This requires having to regularly monitor and adjust the lighting, irrigation, and other environmental factors in response to what the plants need.
Crop steering is a practice in which cultivators manipulate light, climate, and irrigation in an indoor or greenhouse environment to encourage their plants to grow a certain way. Long used in hydroponic vegetable production, crop steering is achieved in part by adjusting the frequency and amount of irrigation specifically for the environment, cultivar, and stage of plant growth. As a result, cultivators are able to steer their plants to grow bigger, produce better quality, and improve yield without losing production.
How Does Crop Steering Work?
The life cycle of the cannabis plant covers the following four phases:
- Propagation: when a new plant grows from a seed, cutting, or tissue culture
- Vegetative: when plants produce leaves, stalks, and shoots
- Generative: when plants produce flowers, fruits, and seeds
- Harvest: when plants are gathered and dried before curing
To achieve healthy cannabis plants in high yields, maintaining a proper balance between a plant’s vegetative and generative growth stages is vital. Growers can use crop-steering techniques to cue their plants to lean more heavily in one direction or the other.
During the vegetative stage, plants are focused on early root and plant development. Growers must maintain proper water content in the root zone without over- or under-saturating the substrate. When steering the plants vegetatively, cultivators are able to promote rapid growth by eliminating stressors and allowing plants to absorb as much water as possible while also ensuring they receive adequate nutrition. They achieve this balance by keeping electrical conductivity (EC) low, and using every irrigation event (shot) as a signal that encourages the plant to take advantage of available resources and grow as much as possible.
During its generative stage the cannabis plant focuses on maximizing flower, resin, and flavor production. While growers apply more shots throughout the day in this phase, water content is typically maintained at lower levels than during the vegetative phase. When steering generativity, growers apply targeted stressors – including increasing EC in the irrigation and the substrate to control water uptake – to promote more compact growth with a greater focus on the parts of the plant that support reproduction.
Putting Crop Steering Into Motion
Crop steering empowers growers to control their environment, make more informed cultivation decisions, and achieve targeted results. To be successful, cultivators respond to generative and vegetative cues in the following key areas:
- Electrical Conductivity (EC): The amount of dissolved fertilizer in a solution as determined by the ease at which electricity can move through the water; EC is a direct measure of the amount of water that roots can access immediately for transpiration and growth. For a deep dive into EC, check out our video.
- Drybacks: The difference in volumetric water content (VWC) - expressed as a decrease in VWC% - from the last irrigation event of a given day (maximum saturation) to the first irrigation event of the following day (lowest VWC level).
- Field capacity: The point after/during irrigation at which a substrate can no longer hold any more water. Check out this video for more about field capacity.
- Leachate: The solution that is not absorbed by the medium during an irrigation event once it has reached its maximum potential saturation; also known as runoff.
- Shot size: The volume applied during an irrigation event, or shot - usually expressed in total volume (mL) or as a percentage of the total media volume. For example: a “3% shot” means the volume of the irrigation water applied is equal to 3% of the total substrate volume.
- Volumetric Water Content (VWC): The volume of water per volume of substrate, expressed as a percentage (%). Check out this video for more on volumetric water content.
- Water Content (WC): The volume of nutrient solution (water + nutrients) in the substrate.
Crop steering is an approach to craft cultivation that allows growers to have greater agency over their plants. Being able to steer plants toward a target outcome doesn’t just empower cultivators - it also makes their lives easier.
That’s our reasoning for developing AROYA, the ultimate cannabis production platform. With sensors that see inside the substrate and a platform that tracks and monitors your grow at every stage, cultivators get all the insights they need to be able to steer their plants successfully.
Ready to Book a demo? Our Client Success Team is ready to walk you through all the ways AROYA can work for you!
And for a deeper dive, check out the AROYA Guide to Crop Steering.
Photo by Richard T on Unsplash