Hemp is the first modern crop to go from underground to mainstream farming, and the soil medium used in conventional agriculture is a whole new world for the closet grower. The best type of soil for growing hemp is sandy-loam with higher levels of phosphorus, calcium, micronutrients, and a pH of 6.2-6.8. Soil should contain high amounts of ammonical nitrogen to provide for good vegetative growth early in the season. Sandy loam soils also contain higher levels of silica, which is speculated to improve cell wall development.
When growing in sandy loam soils you will find less chance of acquiring soil born diseases compared to heavier soils. Finally, you will have more nutrients available in sandy-loam than pure sand soils and have an overall better crop. Other soils are not to be avoided altogether, but with the increased drainage and other characteristics of sandy-loams you will have greater overall success. For success in large-scale outdoor hemp farming, feel free to seek consultation at Western States Hemp.