Conventional
Hemp can be successfully grown under any traditional Canadian conventional production system.Hemp fits in with typical crop rotation systems and with typical equipment that would already be found in a grain production system.
Typical Hemp and small grains seeding equipment
(Video Seeding Equipment)
Zero-till
Zero tillage is a cropping system where the crop is sown into the previous years stubble. Hemp has been successfully zero-tilled in many situations as long as the seedbed is warm, firm and moist to encourage fast, uniform emergence.
Typical seeding equipment for zero tillage
Organic
Hemp’s rapid growth, once established, makes it an excellent crop to be grown successfully under organic production systems. Pre-seed cultivation is often done early to stimulate weed growth and warm up the soils by incorporating residue. Immediately prior to seeding, the field may be worked once again to kill weeds. Good fertility and seeding conditions will ensure the crop has a good start to compete with weeds. Refer to other organic production resources for further detail.
Under Seeding with Forages
Some producers, especially with shorter varieties, will under seed alfalfa and grass seed with hemp in the spring. The forage crop establishes in the shaded micro climate under the hemp plants. In the fall, after the hemp crop senescences and loses its leaves, the forage crop is able to establish itself in preparation for winter. In spring, the field is rolled to flatten the hemp stalks. Leaving them in the field will not interfere with the hay harvest. This gives good snow cover and creates a microclimate that protects forage establishment.
Row Cropping
Row cropping of hemp has been used on a limited basis. To date the majority of hemp has been grown in Western Canada where row cropping is not typical.
The main advantage for using row cropping would be weed control. Row spacings can be adjusted to accommodate the tillage equipment being used.
Row cropping Hemp
Seeding rate can be reduced since the plant population will be denser within the row and the plants will self thin to a sustainable population.
Hemp is a slow growing plant for the first few weeks of its life. Tillage is required when the plants are small so the crop can outcompete the weeds. Care should be taken not to cover the young hemp plants during the tillage operation. More than one tillage operation may be required to achieve a desirable level of weed control. The aggressiveness of the tillage can be adjusted as the hemp plants develop.
Field Selection
Industrial hemp will grow on a wide variety of soil types and conditions. Hemp tends to do best on soils with good fertility and drainage. Hemp can do very well on sandy light soils due to its large tap root that can source moisture and nutrients from deeper in the soil profile.
Heavy clay soils present the biggest challenge to growing hemp. In the early stages of hemp growth, young plants do not withstand cool, waterlogged soils. Soil compaction, which is more prevalent on heavy clay soils, can cause an increase in seedling mortality. Clay soils with poor drainage will remain wet and ‘pond’ water more readily for long periods of time under adverse conditions. If this happens, hemp plants will not do well. Stress in these early stages of plant development can delay crop growth which could result in weed control problems later in the year and potential yield reductions. See Impact of Severe Weather
Events on Hemp Production.
Hemp, after heavy rains and cool conditions will become chlorotic at its center growing point.
Chlorotic growing point due to excess water
The growing point is in the middle at the top of the plant. If this growth point becomes severely damaged in the early growth stages, the plant will likely die.
Plant dying due to growing point damage
Sunny hot conditions after a heavy rain usually means the plants will recover.
As the crop grows and becomes mature and taller (after about 50 cm (20 inches)), it is able to withstand and recover more readily from heavy rains and cool conditions.