Medicinal Cannabis Blog #2
by Jim Hole
Cannabis is referred to as a ‘short day’ plant. What this means is that most cannabis varieties require day lengths that are equal to - or shorter than – nights, before they are capable of flowering.
At the Atlas Controlled Environment facility, plants are grown under long days (18 hrs or more) until they reach sufficient size and then the lighting program is switched to 12 hours of light and 12 hours of continuous darkness right through until harvest.
When cannabis plants experience short days, flowers are initiated and buds swell, producing a rich mix of medicinal ‘phytochemicals’. The science of short days and flowering is pretty straightforward but the art of knowing the best timing for switching the lighting is variety dependant.
Switch too early and yield is compromised. But switch too late and cannabis earns its nickname ‘weed’ because the plants become giant masses of stem and foliage and extremely hard to control even with diligent pruning.
Cannabis varieties remind me of tomato varieties. Some grow slowly and have more of a ‘mounding’ habit while others would grow to the ceiling if you let them!