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.
Terry County July 2020
Terry County late May 2020
No till is a cropping system where the crop is sown into the previous years stubble. Hemp has been successfully no-tilled in many situations as long as the seedbed is warm, firm and moist to encourage fast, uniform emergence.
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.
HEMP STALK AS COVER CROP
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 microclimate 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 cover and creates a microclimate that protects forage establishment.