Hemp is showing up in farm fields across Colorado, gaining a reputation as a valuable, supposedly drought-tolerant cash crop. But is the plant really ideal for a state facing water shortages?
Colorado is about to find out. Thanks to hemp’s removal from the Controlled Substances Act last year, as part of the Hemp Farming Act of 2018, researchers finally have almost free rein to examine how it performs with and without water, and what can be done to boost its value and water-saving qualities.
Hemp is the non-psychoactive form of cannabis and it has a complicated history in the United States. Many of the founding fathers grew hemp and praised the plant as a cash crop, until a 1937 tax law essentially made the plant illegal. During World War II the U.S. government changed the rules again, begging farmers to grow hemp in a propaganda film called Hemp for Victory.
And now, after decades on the shelf, Colorado farmers are bringing it back, with thousands of acres under cultivation.
Katie Russell, manager of Colorado State University’s Southwestern Colorado Research Center, is one of multiple groups doing extensive study on hemp’s drought tolerance. Right now, Russell says hemp may be getting more credit for tolerating dry conditions than it currently deserves.
“I don’t think that this is a dryland crop for our area because we do have such low rainfall and it’s very variable amongst seasons. So, it could be very risky some years and could work out other years. It’s probably on point with corn. If you look at a perennial system, alfalfa for instance, it would be a water savings in comparison,” says Russell.
Part of the problem is that very little research on hemp exists because until this year the plant was mostly off-limits to farmers and scientists. But now, researchers like Russell are free to look into ways to help boost the plant’s value and hardiness.
“I think we could really improve hemp as a drought crop,” Russell says. “I think as we move forward in the future, if we’re really targeting that at as a specific breeding purpose then I think we could find it could work in a lot more arid environments.”
CBD, an oil extracted from hemp flowers, is used in a wide variety of popular products marketed for calming, healing and health. Hemp fibers in the plant’s stalk are used in items like clothing, rope and paper. Russell says regardless of the end-use, hemp farmers may be less likely to minimize hemp’s water consumption when they see how much better the plant performs with more water.
“We’re seeing larger growth habit with the higher water—greater stem diameter, more branches—which would likely then be more flowers and should equal more yield. If this were a fiber system, something that really relies on high biomass, I think you’d see a pretty good yield reduction under the lower water use scenario.”
Though the variety of hemp plants currently available may not deserve the title of drought-tolerant on their own, the hemp boom is inspiring a new wave of creativity in agriculture with a focus on saving water.
Jason VonLembke, project manager for the Subsurface Irrigation Efficiency Project or SIEP, says the hype around hemp is pulling water-saving irrigation techniques out of the shadows and into the mainstream spotlight. “One of the cool things is that it does draw younger people in who are kind of open to these technologies. So, if anything, you might see a jump in people using efficient irrigation.”
And studying water efficiency in agriculture is exactly what VonLembke and the SIEP team do at their research facility in Kersey, where the primary focus is 82 acres of subsurface drip irrigation. This system pumps water from a well through a filtration system that can add nutrients to the water before delivering it directly to the roots of rows of hemp planted on mounds.
“If you’re irrigating with flood irrigation your crop is absorbing about 45 percent and the other 55 percent of that water is either runoff or it evaporates. If you’re using a pivot circle your efficiency is around 80 percent. So, what we’re trying to do with drip irrigation is get those efficiencies up to 95 to 98 percent,” VonLembke said.
SIEP researchers are growing hemp because it does well with subsurface drip irrigation and its value makes the high cost of switching to the water-efficient drip system more feasible. “The system is expensive. It costs about $1,500 to $1,700 an acre. We have been growing alfalfa here for the last three or four seasons. Prior to hemp we believed alfalfa was one of the most valuable cash crops because you can get about $130 to $140 a ton for it. But we can sell our hemp flower at $35 a pound.” That is the equivalent of $70,000 per ton.
SIEP is studying other less expensive, non-traditional forms of irrigation that also work well with hemp.
Their mobile drip system is a more accessible water-saving design that uses a traditional pivot irrigation system, the type you see on most farmland working its way across the field watering crops from above. But this one has hoses or drip lines attached to each nozzle delivering water directly to the ground around the plants as it moves. “I’m so excited about this. I think this is one of the immediate answers,” says VonLembke.
An hour and a half away in Sterling the Lebsock hemp farm is testing irrigating hemp with drip on a major scale.
David Lebsock and his family are growing a thousand acres of hemp for CBD. Their entire crop is irrigated on a subsurface drip system. They’re hoping drip will save them 40 to 50 percent of their water.
Lebsock says another benefit of drip irrigation is that it allows the family to use more of its land. The Lebsock team believes they are still using less water even though they’re using more of their space. “I mean, right now we haven’t watered for the last week,” says Lebsock. “Does that plant look like it’s droughty? Not at all.”
An earlier version of this story aired on Connecting the Drops, a radio program produced in partnership between Water Education Colorado and Rocky Mountain Community Radio stations. This series is sponsored by CoBank, a national cooperative bank helping to provide financing solutions for rural water systems.
Hannah Leigh Myers is an award-winning multimedia freelance journalist working on Colorado’s Front Range.