Hemp is a valuable oilseed crop grown for its grain. It is historically dioecious (separate male & female plants). Hemp varieties have exhibited considerable differences in height, maturity and seed size. Hemp grain varieties bred specifically for a higher harvest index (more and larger seeds on shorter plants) in Western Canada include Picolo, Katani, Grandi, CFX-2, CFX-1, CRS-1. Maturity ranges from 100 to about 115 days. A hemp bushel weighs 44 lbs, or approximately 260gm /.5L.
Hemp grows best on clean, fertile, medium textured soil, on cereal or pulse crop stubble that is free of herbicide residues. Organic hemp crops are best preceded by perennial alfalfa breaking or a GM plow down (i.e. SSNS-1 fababeans).
Seed hemp shallow, but into moisture(0.5 ~ 1.0+ inches), ideally after the soiltemperature has reached 8 ~ 10C+. Hemp is quite frost tolerant. Averageseeding dates for hemp vary from late
May to mid-June. Expect germinationin 2 to 4 days and emergence within 4 to 7 days. Reduce airflow on air distribution systems to prevent seed damage. Seeding rates are 25 to 30lbs / acre, and expect approximately $50 to $60 / acre seed cost. Government regulations require use of pedigreed seed.
Hemp responds very favorably to adequate fertility, but is very sensitive to higher rates of any nutrient placed close to or with the seed. Conventional producers should fertilize with rates similar to canola, but with at least 10 - 20% more N. Organic producers are recommended to precede a hemp crop with a perennial alfalfa breaking or annual legume green manure plow down. Hemp yields are usually about 60% of dryland canola, conventional crops averaging 20 to 30+ bu/acre, yields are considerably higher for irrigated crops (+50% up to 3000lbs) and more variable in organic crops.
Weed, Disease & Pest Management
Weeds are best controlled through proper field selection, a pre-seeding burn-off, adequate rates of fertility, and selecting the proper hemp variety based on height. Hemp has few disease and pest problems. Hemp has limited susceptibility to sclerotinia / botrytis in wetter years. Note registered herbicides are limited, as only Assure II has been registered for grain production in Western Canada, and other pesticides trials are ongoing thru the Minor Use program.
Harvest, Drying & Storage
Most producers prefer to straight combine hemp while it is still “green / immature” to minimize stem fiber wrapping. Depending on variety and combine, thresh from 11% to 17% moisture (dry is 10% - stores best at 8%). Minor fiber wrapping may occur depending on hemp variety and field conditions with 15-20 year old combines i.e. JD 9600’s / CIH 2188’s, and very little or none with the newest, i.e. CIH 8 series / JD S series. Dry or aerate hemp grain immediately off the combine to 8%, heated air works well. “Turn” and or aerate hemp grain at change of seasons (spring / summer) to reduce moisture migration / spoilage. Move and unload hemp at reduced auger speeds using large diameter augers or belt conveyors. Cut or “haybine” remaining stubble within a few days and bale at 12% moisture, or alternately incorporate with heavy duty disc to clean up field for next year’s crop.
Licensing & THC Sampling
Each year producers are required to apply for a cultivation license with Health Canada. One license will cover all cultivation sites and activities. A criminal record check must accompany your application. Applications will be now be accepted electronically via email. Growers will be required to identify their hemp fields within 14 days of seeding by submitting a map and GPS coordinates
to Health Canada. THC testing for commercial production for most hemp varieties has been eliminated provided the variety is on a list of approved cultivars. THC testing is still required if growing pedigreed seed. The expiry date of a license has been extended until March of the following year to allow for the sale of products grown in the previous year.
Please contact the Industrial Hemp Section for a copy of the Application for an Industrial Hemp License and any additional information on the Industrial Hemp Program.
Industrial Hemp Section
161 Goldenrod Drwy
Ottawa ON K1A 0K9