When it comes to growing cannabis, irrigation tends to get less attention than the flashier aspects like lighting and nutrients. Irrigation is a critical piece of the cannabis cultivation puzzle, but the fact that you can just do it by hand allows people to overlook the benefits — both to the bottom line and to the plants themselves — of installing an irrigation system. After all, hand watering has gotten the job done for decades of clandestine cultivation, so why fix something that isn’t broken?
The answer to that is simple, although proponents of hand-watering may not like it. The fact of the matter is that hand-watering is broken if you’re a commercial cultivator. It costs too much in both time and money and is horribly imprecise. Spending some extra time and money up front to install an irrigation system is not only a surefire way to decrease operating costs in a highly competitive industry, but it will also give growers much finer control over the amount of water and nutrients their plants receive compared to hand-watering.
There are a number of different types of irrigation systems available to cannabis growers, but in the discussion of maximizing cost savings and efficiency, drip irrigation is really the best solution.
At its heart, drip irrigation is the slow, precise application of water directly to the roots of a plant. Despite it being called “drip” irrigation, this application of water can come in the form of a spray, a mist or the titular “drip-drip-drip” of a standard drip emitter. While traditional sprinklers consume water in gallons per minute, and hydroponics techniques — such as flood and drain — have no flow control to speak of, drip emitters are engineered to emit a specific amount of water, usually measured in gallons per hour. It is this simplicity of concept and precision engineering that allows drip irrigation to offer so many benefits to the cannabis grower.
On the surface, hand-watering seems like a good deal. People need to be out among the plants to keep an eye on them anyway, so why not have them water the plants at the same time? The personal touch of an experienced gardener is a rare commodity that growers are always looking for. Add in the sentiment of “that’s how we’ve always done it” and there’s a powerful — if misguided — case for hand-watering cannabis.
That case begins to break down upon closer inspection, however. Watering plants by hand takes a lot of time, and time has a knack for being the most expensive part of any business. It is true that you need people checking in on the plants, but how much time do they have to give them the TLC they deserve when they spend most of their time mixing nutrients, weighing, watering and reweighing? The larger an operation grows, the less time its employees have to nurture the plants. Paying people to water by hand costs increasingly more money as an operation grows. This is doubly true when it comes to experienced growers. Not only do they cost more to employ, but their skills could also be put to better use than ferrying water from one place to another.
Charles Johnson, chief operating officer of Truly Oreganic, a cultivator in Oregon, said he was extremely happy with the shift from hand-watering to an automated system.
“It has turned a four-hour job into 20 minutes,” Johnson said. “The drip system waters all plants exactly the same, no matter what location in the system.”
The Precision of Automation
In a perfect world, an employee may be able to water plants and have time left to sing “Stairway to Heaven” to all the mothers as they coax them toward their grid of artificial suns, but anyone who has grown cannabis knows that we don’t live in a perfect world. Cultivation involves rolling with a never-ending series of punches. The already time-consuming process of hand-watering is exacerbated by heavy plants, unruly growing media (such as expanded clay balls) and crowded grow rooms that restrict maneuverability. The amount of nutrients and water delivered to each plant is largely at the whims of the employee doing the watering, and this imprecision can breed time-consuming problems of its own, such as nursing over- or under-watered plants back to health.
Replacing your watering brigade with a drip irrigation system solves many of these problems outright. Installation of a properly-designed drip system can be done quickly by a trained professional, or slightly slower by a complete novice. Think of it like Legos: all the pieces may look intimidating when strewn across the floor, but with a little explanation and some sorting, everything logically clicks together (just make sure you don’t step on them with bare feet). Enlisting professionals during the design phase is a must, though, as badly designed systems are the stuff of nightmares.
Drip irrigation systems are also extremely precise and, with the proper automation system, they can be reliably turned on for as little as one second at a time, dozens of times per day. This allows growers to measure the nutrients and water each plant receives down to the milliliter. That’s not to say that an experienced grower can’t do this by hand, but an automated drip irrigation system will do it all by itself, without an hourly paycheck.
You may be reading this and thinking, “this all sounds really expensive,” and you wouldn’t be wrong. Many products made for the cannabis industry have an inflated price tag due to the history and risk associated with the plant. Drip irrigation systems as we know them today have been around since the mid-1960s and thus avoid the typical markup associated with cannabis-specific products.
It is not uncommon for a drip system to cost $1 per plant, including basic automation. Integrated nutrient injection and soil monitoring are more expensive, but for grows large enough to merit those technologies, the cost-per-plant still remains low. The cost for these systems is all up-front, unlike the ongoing costs associated with retaining employees to hand-water plants, allowing businesses to amortize the cost across the whole life of their system. Considering that many drip irrigation products are designed to operate in outdoor, agricultural settings for upwards of 20 years, that cost could be amortized for quite a while.
While irrigation may be the most boring aspect of a grow facility, it is essential to making an operation profitable. The cannabis industry is steeped in decades of myth and tradition, and while that’s one of the things that makes it fun to work in, it can also hamper the adoption of important technologies. Your dad and your dad’s dad may have watered their weed by hand, but commercial facilities ain’t your daddy’s grow op. For anyone looking to succeed at large-scale cannabis cultivation, a proper irrigation system is a must. Your bottom line — and your back! — will thank you.
Erik Luchsinger is a system designer at Cannabis Irrigation Supply, a family owned firm with more than 35 years of experience in the irrigation industry. His hobbies involve writing, history and annoying his brother, Sam. He can be reached by email at firstname.lastname@example.org.