Know your varieties, talk with other growers, do your research and use your best land. Those are hemp agronomy tips from Kevin Friesen, seed production manager with Hemp Oil Canada and a partner with Hemp Genetics International.
Friesen, who spoke at the Canadian Hemp Trade Alliance conference has been in the industry since 2001 as a pedigreed seed grower, working primarily with grain and non-fibre varieties of industrial hemp.
Most hemp grown in Western Canada is grown for grain production, although there is dual-purpose production as well. Canada grew 52,560 acres of hemp in 2012, of which 24,700 were in Saskatchewan, 12,958 in Manitoba and 12,602 acres in Alberta. Those precise figures are possible because anyone who wants to grow hemp in Canada has to apply for a licence from Health Canada. Depending on the variety, many producers will have to have their crop tested to be low enough in THC, the compound which produces the “high” from marijuana varieties.
Friesen said the hemp industry has grown by about 35 per cent each year for the last few years. “I think that reflects the markets for hemp. The retail side is maturing because companies are contracting in a responsible manner.”
He said growers often run into problems if they grow hemp on spec. “Work with the company, produce under contract and get your licensing in place,” he said. “Make sure you have the right agronomic information.”
Varieties sensitive to area
Hemp varieties react differently in various locations. “Finola, for example, will grow nine feet tall in the Peace River area but will grow only 2-1/2 feet tall in Ontario. Not every variety is the right match for every grower in every location,” Friesen said.
Finola is the main variety grown in Alberta. It’s attractive because it has a short growing season and a short stature. The variety is small seeded, easy to harvest and matures in 100 days. It is well suited to irrigation, can be swathed and does well in northern climates.
Friesen said the second most popular variety is CFX-2. This variety and its similar counterpart, CFX-1, have moderate height, moderate growing season and a large seed size. “As hemp varieties get taller, harvest tends to get a little bit more difficult,” said Friesen.
The third most popular variety, CRS-1, is grown primarily in Manitoba, takes 110 days to mature and has a large seed and high yield. “I kind of call that the full-season grain variety,” Friesen said.
Dual-purpose varieties include Delores and Alyssa. These varieties produce more biomass, are longer season and are large seeded and high yielding.
“You have to realize that not every variety fits everyone and you have to be careful to choose what works for your area,” said Friesen.
He recommends growers get professional advice and find out what other growers in their region are doing. It’s important to grow hemp on the best land available.
Friesen said hemp can be grown successfully using organic or conventional methods.
Producers who go organic should choose high-fertility, medium-textured soils with good drainage. Row cropping works well in organic dryland situations. Conventional farmers should plan to add as much fertility as they do when growing canola. Adding extra fertilizer helps growers deal with weed pressure from wild oats.
“Fertility is really the key to growing this crop and it’s also your herbicide,” said Friesen.
Finding the optimal plant density and seeding date can help producers cope with weed pressure. Friesen said the industry has to work to get minor use herbicides registered for hemp, and some herbicides do work well on the crop.
Friesen said hemp does not have many disease problems, but can develop sclerotinia under humid conditions. It’s not known if clubroot is a risk. Pests are not a large issue, but bertha army worms have been known to defoliate the plant.
Harvesting hemp is the most challenging part of the growing process. “It’s really important to take it off at the right time, which can be different from year to year,” said Friesen.
Generally, the crop is harvested when it is green, which minimizes fibre wrapping in the combine. Shorter-season varieties are taken off at lower moisture.
Most producers straight combine. Hemp needs to be cut cleanly in order to prevent it from bunching up and creating havoc inside the combine.
Strong wind can shatter heads on a mature crop, so to manage this risk, many producers in southern Alberta grow short-season varieties and swath.
“The advantage is that you have dry seed. The disadvantage is that you do put more fibre through the combine,” Friesen said.
He recommends grain dryers or the use of an inline heater between the fan and the bin, as hemp has a strong tendency to spoil if it is not dried efficiently.
Growers who are not selling their fibre will have to figure out how to manage it. Some bale it, some incorporate it and others rake it with heavy harrows.
“At the end of the day, it’s either a bale or a match that takes care of it and gets it off the field,” Friesen said.