The Imperial Valley of southeastern California is known for several crops such as alfalfa, lettuce, sugar beets and carrots. But ag researchers have been tasked with looking into the potential for growing new crops, like Rhodes grass as a forage crop and, more recently, industrial hemp.
Seed companies approached Oli Bachie, agronomy adviser for Imperial, Riverside and San Diego counties, and director of the University of California’s Department of Agriculture and Natural Resources station in Imperial County, to look into the potential of growing hemp in the region.
The interest is based on the versatility of hemp, which can be made into different products — biodiesel, fiber, textiles, clothing, food and nutritional supplements. It’s also because cotton is no longer grown in the Imperial Valley, and hemp could be a potential replacement crop that consumes a lot less water than cotton.
If it shows potential, it would be grown primarily for seed and fiber.
Industrial hemp and marijuana are often lumped together, but hemp is different in its contents. A marijuana plant has 15% to 20% tetrahydrocannabinol — THC — the active ingredient that gives pot consumers a high.
Hemp can be classified as industrial only if it has a 0.3% or lower level of THC.
Bachie will get input and advice from growing programs in Kentucky, Michigan and other states. So far, he’s looked at the morphology and anatomy of hemp, which is technically Cannabis sativa, but expects to learn the rest through field experiments.
Bachie explained how there are some misconceptions about the environmental conditions needed to grow hemp. Some think it can thrive only in cool weather, while others think it has evolved to adapt to hot desert conditions with low rainfall, and this will be part of the trial’s focus.
“The plant produces dry combs, hairy structures on the leaves that help reduce evapotranspiration from the surface,” Bachie explained. “Industrial hemp has deep tap roots. When there’s a shortage of water, it sends roots deeper to extract water from underground.”
It needs well aerated loamy soil, with a lot of organic matter in it. Hemp is an annual plant, so after every harvest it would need to be replanted.
It takes four months from planting to maturity and can yield as much as 8,000 pounds of seeds per acre, depending on the variety, the soil and weather conditions and the resources given to the plant. Research shows it can be grown in different situations.
Hemp is sensitive to photoperiods, so it flowers if the length of day is shorter. It also needs shorter days, with less than 12 hours of light.
The trial will explore how much daylight it needs and which seasons are best. Most hemp today is grown in cool environments, but it can adapt.
“We have seen that Nevada, Arizona and Colorado have begun growing industrial hemp. Imperial Valley is similar in conditions to Nevada and Arizona. If they can do it, we may have the potential to grow it here,” he said.