Seeding too early can cause seedling mortality due to cold soils and pathogens. Ideal seeding dates for hemp production in Minnesota are between mid-May and mid-June. Soil temperatures should be at least 45- 50 degrees Fahrenheit. When growing for CBD production, many growers will transplant seedlings or clones into the field.
General seeding recommendations is between 20- 40 lbs per acre for grain production, and 40- 60 lbs per acre for fiber production. The populations of grain- and fiber-type hemp varieties will have a mixture of roughly 50/50 males and females. A lot of factors go into determining the optimal seeding rate for your field, including the variety, seed purity and germination, local conditions, etc. Most conventional drills and seeders will work for hemp. Use lower air volumes to avoid seed cracking. Seed shallowly (0.5”-1” maximum) into a firm seedbed. Avoid soil compaction and do not seed before a large rain event.
For CBD production, the plants are spaced much less densely, generally 1000- 2000 plants per acre. The plants are widely spaced to encourage branching and maximum flower development. CBD is produced in the female flowers. Only females are grown and male plants are removed to prevent pollination. If the female flowers are pollinated then the plant will put its energy towards seed production, and not cannabinoid production.
General seeding recommendations is between 20- 40 lbs per acre for grain production, and 40- 60 lbs per acre for fiber production. The populations of grain- and fiber-type hemp varieties will have a mixture of roughly 50/50 males and females. A lot of factors go into determining the optimal seeding rate for your field, including the variety, seed purity and germination, local conditions, etc. Most conventional drills and seeders will work for hemp. Use lower air volumes to avoid seed cracking. Seed shallowly (0.5”-1” maximum) into a firm seedbed. Avoid soil compaction and do not seed before a large rain event.
For CBD production, the plants are spaced much less densely, generally 1000- 2000 plants per acre. The plants are widely spaced to encourage branching and maximum flower development. CBD is produced in the female flowers. Only females are grown and male plants are removed to prevent pollination. If the female flowers are pollinated then the plant will put its energy towards seed production, and not cannabinoid production.
Yes, you can grow certified organic hemp on organic land just as you would any other crop. The National Organic Program (NOP) does allow organic certification of hemp grain and fiber. They have indicated they may not certify cannabinoid extracts produced from hemp, but each local certifier may handle this matter differently. Please visit the MDA's Organic Agriculture website, the USDA/NOP website or contact a USDA Accredited Organic Certifier for more information.
Currently, no pesticides are labeled for use on hemp in Minnesota.
Yes, you can grow certified organic hemp on organic land just as you would any other crop. The National Organic Program (NOP) does allow organic certification of hemp grain and fiber. They have indicated they may not certify cannabinoid extracts produced from hemp, but each local certifier may handle this matter differently. Please visit the MDA's Organic Agriculture website, the USDA/NOP website or contact a USDA Accredited Organic Certifier for more information.
Currently, no pesticides are labeled for use on hemp in Minnesota.
Yes, hemp has similar nutrient needs as canola and especially requires added nitrogen. Fertilize like rapeseed (Canola- Brassica napus) with 15% additional nitrogen. Conventional NPKS (nitrogen, phosphorus, potassium and sulfur) fertilization is recommended at the same levels required to grow rapeseed. Apply additional K and S wherever soils are deficient in these elements.
Yes, hemp has similar nutrient needs as canola and especially requires added nitrogen. Fertilize like rapeseed (Canola- Brassica napus) with 15% additional nitrogen. Conventional NPKS (nitrogen, phosphorus, potassium and sulfur) fertilization is recommended at the same levels required to grow rapeseed. Apply additional K and S wherever soils are deficient in these elements.
Hemp grain harvesting is generally done by straight combining, however swathing is also used. Visit the University of Wisconsin Extension's Industrial Hemp Agronomics guide for more information on hemp harvesting.
For CBD production, harvest is usually done by hand by cutting the whole plants and hanging in a barn to dry. Some growers will mechanize the process by modifying combines or other equipment to strip flowers/biomass from branches and then dry quickly with industrial dryers. Green flowers and biomass will heat and spoil quickly if not properly dried within hours of harvesting.
Hemp grain harvesting is generally done by straight combining, however swathing is also used. Visit the University of Wisconsin Extension's Industrial Hemp Agronomics guide for more information on hemp harvesting.
For CBD production, harvest is usually done by hand by cutting the whole plants and hanging in a barn to dry. Some growers will mechanize the process by modifying combines or other equipment to strip flowers/biomass from branches and then dry quickly with industrial dryers. Green flowers and biomass will heat and spoil quickly if not properly dried within hours of harvesting.
Generally, for grain-type varieties, crop maturity is between 90- 120 days after planting, depending on the variety and local climatic conditions. Hemp grain/seed is harvested when approximately 75 percent of the seeds are ripe and it starts to shatter. High winds can accelerate shattering. Bird predation can also be a major problem. Recommendations are to harvest at 18-20 percent moisture and immediately begin the drying process. Dry grain to 8-10 percent moisture for storage. Visit the University of Wisconsin Extension's Industrial Hemp Agronomics guide for more information on hemp harvesting.
When growing hemp for CBD production, the grower should be testing the crop regularly for CBD and THC levels. For most varieties, flowering is triggered by changes in day length. However, there are some auto-flowering varieties that are day-length independent and will flower after a set number of days. Most high-CBD varieties will flower for about 6 weeks before harvest occurs, typically at the end of September or early October. Most CBD growers will test their crop weekly during flowering. The goal is to harvest at the time when the hemp is at the peak CBD levels, but still under 0.3% Total THC.
