Manipulate light and increase greenhouse production

Posted on 
May 1, 2020

We hear a lot about GMO crops and about manipulating DNA to treat diseases. The same thing happens when you grow cannabis in a greenhouse whether or not it has computer vision.

Without getting too technical, cannabis is considered a short-day plant, much like chrysanthemums. For them to flower, they need at least 12 hours a day of darkness. Here’s where it gets tricky. The trigger for all this is called phytochrome and before a large enough cannabis plant flowers, it has to accumulate a certain amount of phytochrome.

If not, you just end up with a huge cannabis tree and that’s not very useful unless you want an expensive shade plant.

Suppose you’re the one responsible for a huge Christmas order of poinsettias. Well, you better be certain that when your customer’s truck comes to pick them up, they’re full of nice, bright red flowers. That’s why understanding light is so critical. Growers can manipulate when the plants flower as well as how quickly it takes them to flower.

As important, understanding light also allows you to match your production schedule to the plant’s natural process. If your cannibis is on an eight week cycle, you need to learn how to use lighting to manipulate that phytochrome level and basically help the plant into thinking it’s time to flower.

Going back to cannabis, if you harvest it too early a user feels anxious and if you harvest it too late the user feels drowsy, neither of which is what your vendors usually want.

The single biggest influencer on the overall growing process is lighting which is why cannabis greenhouses have darkening shades. And as we now know, more light doesn’t equate to more growth or at least the kind of growth you want. It’s the nanometers the bulb puts out that’s a more accurate measure. You could have a 1,000-watt bulb but if it’s out of the proper spectrum it’s no better than having a 600-watt bulb. Your greenhouse software should tell you when it’s degrading. Change your bulbs more often and you retain the effectiveness.

To sum it up, proper lighting allows you to mimic the process that allows a cannabis plant to go into flowering the fastest.

As we said above, the thing that controls flowering is phytochromes. If you have proper lighting, you can control phytochromes; control phytochromes and you control flowering. Theodore Huggins, former horticulturist at Crop King put it this way; “Control flowering and you can meet or exceed your production schedule and if you somehow get ahead of the process, by adjusting lighting you can even slow the plant down to meet your schedule.”