Medicinal Hemp is a row crop
Growing hemp for cannabinoid production should be planted as a row crop. Since each plant is so valuable, growers want to maximize the plant's size and resin production. One of the best, easiest and cheapest ways to accomplish this is to ensure that full sunlight is shining on the plants from all directions. For cannabis to really grow great, sunlight has to shine directly on the buds. Flower that grows in the dark will generally end up as 'larf'; fluffy, lime colored buds with little resin.
The following field planting layouts show what fields will look like when planted on 4 foot, 5 foot and 6 foot centers. We have created an example one acre square field that measures 210' X 210'. The area is completely filled with plants. When laying out an actual field you have to make adjustments for fences, roads, drainages, buildings, ponds, etc., so this is for an imaginary acre that is completely planted from end to end.
We have chosen to layout the fields using the triangular system, where plants are placed midway between the plant in the adjoining row. This provides increased open space for sunlight as well as 15% higher plant density per acre than a square or rectangular system layout.
Planting on 4 foot centers
If the strain you're planting grows compactly, matures quickly or planting is late, you might want to set up the field on 4 foot centers.
This layout requires a lot of plants, 2,601. 1,100 more per acre than planting at 5 foot centers.
The mulch bed would be 24 inches wide so the path between rows would be 24 inches wide also.
If the plants grow four foot wide, it would be difficult to walk down the rows. Three foot wide plants would be about right.
Planting on 5 foot centers
I think most growers will lay out their fields on 5 foot centers. Normal growing plants that were vegetated for awhile will would be suited for this layout.
A whole acre is planted end to end, 1681 plants would be required. We tell customers around 1,500 plants per acre.
If the plants grow four foot wide, the two foot path could be easily walked. On five and six foot centers, the mulch bed would be three feet wide, pretty much as wide as can be made with 60 inch plastic mulch.
If the plants grow four and half to five feet wide it will be difficult to walk down the rows.
Planting on 6 foot centers
Planting on six foot centers ensures that walking down the rows will be easy because the path is 3 feet wide.
An end to end planting would require only 1156 plants.
If the plants grow up to five foot wide there will be plenty of room to work.