Growth Cycle
It is important to know that hemp is what’s known as an “Obligate Short Day Plant”, meaning the plant requires daylength shorter than a certain critical length, in order to trigger its flowering cycle.
Because of this, hemp has two distinct growing cycles. The vegetative growing cycle and the flowering cycle.
During the vegetative cycle, the plant is solely focused on creating more plant matter for itself, so the longer the vegetative cycle, the bigger the plant will grow.
Vegetative growth happens during “long days” which consist of 14-15 hours of daylength for most Cultivars.
During the flower cycle the plant puts off its flower buds (colas) and produces the sticky resin where the CBD lies.
Most hemp plants will “trigger” their flowering cycle when daylength decreases to 14 hours or less.
It is important to note that daylength is vastly different across the various growing regions where hemp is cultivated and the critical time period is different for the many different strains of hemp.
So a particular cultivar of hemp that grows fantastically in Wisconsin, may not grow well or at all in Tennessee.
Regardless of whether you grow hemp from seeds or clones, all plant material must first go through a “rooting or germinating stage” where it creates a root ball around the media it is started in. The process takes approx. 5 – 6 weeks.
The plant material then, either a seedling or a clone, is planted in the field during late spring or early summer when the daylength is long enough to ensure the plant will continue its vegetative growth cycle.
During the summer months, the plant grows rapidly in body and height, putting on a lot of leaf matter and size.
As the days get shorter (less then 14 hours for most cultivars) hemp will then be “triggered” into its flowering cycle and it will begin to form white hairs or pistols that form the flower buds. Vegetative growth is significantly slowed during this time and the plant focuses most of its energy into producing the flower bud and resin.
The longer the plant stays in the flowering cycle, the more resin it produces, which also increases the CBD % and THC% content.
Harvesting
This time varies from 7 – 10 weeks depending on cultivar and weather conditions the plant experience during this time.
When Hemp plants are harvested, the plant material needs to go through a drying and curing process. This process eliminates the rest of the water content the plant collected during its lifecycle, and the density of what is left, is the oil resin that the buds produced during the plant’s flowering cycle. More resin = more oil for extraction = more profits for farms.
It is important to choose the correct cultivar for each specific growing region. It’s not so important as to what the CBD % is on a cultivar, but rather which cultivar will allow you to maximize your resin production per acre. The higher the resin content, the heavier the plant will be, thus resulting in more bio-mass lbs. per acre. 3,000 lbs. of 10% CBD content is worth more then 1,000 lbs. of 25% CBD content.