GROWING CONDTIONS AND REQUIREMENTS
Hemp grows best in an humid environment with a temperature range between 14 C and 27 C. Growth is best if soil is well drained and free of acidity. Plenty of rainfall, especially in the first six weeks of growth is very beneficial. Dry conditions can be tolerated when the plant is established, but whilst in the growth period can lead to hastened maturity and dwarf growth, ultimately reducing yields.
"The proportion of stem biomass and content of the more valuable bast fibres in the stem increases with plant density, therefore dense crops are usually desired."
If hemp is grown for fibre, the recommended seeding rates vary between 200 and 750 plants per square meter. When grown as a seed source, seeding density is between 5 and 120 plants per square meter.
Unless plant density is very low (10 to 30 plants per square meter), hemp crops supress weeds and thus herbicides are not required. Hemp is also less prone to pests and disease so does not need pesticides and herbicides.
Hemp does make heavy nutrient demands on the soil, extracting more nutrients than grain crops- it removes approximately 2 to 3 times as much nitrogen, 3 to 6 times as much phosphourous and 10 to 22 times as much potassium- owing to a fast biomass production. However, with harvest and the process of retting most of these nutrients are returned to the soil counteracting this extraction. The nutrient is recycled by stripping the leaves in the field and leaving them there to return to the soil.
