Indoor marijuana growers spend a lot of time and money on hydroponics grow lighting.
For many years, we’ve been told that the 18/6 hours per day grow room lighting program is the right light cycle to use for veg phase.
One justification offered to support the 18-6 lighting program was that marijuana plants allegedly need a dark period every 24 hours.
We were told that if marijuana plants don’t get a dark period every 24 hours, they have problems with metabolic processes and can get “too tired.”
We were told that 24 hour per day lighting doesn’t make grow phase marijuana plants grow faster or better, so the extra hours of light are wasted electricity.
We also assumed that six hours of marijuana grow room darkness per day lowers your electricity bills, and it lowers your marijuana grow op temperature whenever your lights are off.
But discoveries made by marijuana researchers at the hydroponics company Advanced Nutrients indicate that marijuana plants don’t need a dark period during grow phase.
As long as your cannabis plants receive adequate C02, water, and nutrients, they’ll engage in photosynthesis and other metabolic functions as long as your lights are lit.
In other words, when you give grow phase marijuana plants the right environment and the right inputs, they can “eat” 24 hours of light per day. The results: faster growth, earlier maturation, stronger/healthier marijuana plants.
Several members of the BigBudsMag.com cannabis grower team have experimented for years with 24-hour light cycles in grow phase.
One of our growers was cultivating Lemon Kush marijuana plants. He did a side by side comparison with Lemon Kush clones, using an 18-6 light cycle and a 24-hour per day light cycle with HID metal halide lighting.
The 18-6 plants were mature enough to be flipped into bloom phase after 8 weeks of veg phase growth.
Cuttings from the same Lemon Skunk marijuana motherplant grown under 24 hours per day of continuous light were ready for bloom phase after six and a half weeks of growth.
When you look at electricity costs for these two approaches, you see that the 24 hour lighting program cost 42 hours a week of extra electricity for the lights, and 42 hours of weekly extra air conditioning costs to remove the heat from grow lights.
The marijuana plants use more water and nutrients during the 24 hour per day light cycle than they would have if they were on an 18 hour per day light cycle.
But because the Lemon Skunk plants finished 1.5 weeks faster, the 24-hour per day program resulted in avoiding the need for a week and a half of light.
By getting to grow phase maturity earlier, the grower saved 18 hours of lighting per day for 1.5 weeks, which equals 180 hours of light he didn’t have to use.
Grow phase was shortened by 1.5 weeks, resulting in lower electricity costs, and less costs for water and nutrients.
Going deeper into the benefits of 24-hour lighting, you find that shortening your grow phase by 1.5 weeks enables you to accelerate your harvest schedules per crop and potentially harvest 10-30% more marijuana per year, without an increase in production costs (and maybe a decrease).
One of our growers ran a 24 hour light cycle from the start of grow phase to the start of bloom phase, adding C02 at 1100 ppm.
He upped the parts per million of his pH Perfect hydroponics base nutrients feed program by 17%, and saved climate control money by not having to keep his grow op temperature as low as normal (when you add C02 in a grow room with correct humidity, your plants can handle warmer temperatures).
His marijuana plants were ready for bloom phase 14 days faster than they would have been if he’d used 18-6 lighting.
He reports his marijuana plants had thicker stalks and produced and supported heavier buds than previous crops.
Another benefit of 24 hour per day grow phase lighting: when you switch your marijuana plants to 12-12 bloom phase lighting, they tend to start flowering faster and have more budding sites, especially if you use a bud stimulant product called Bud Ignitor.
We’ll share more hydroponics lighting marijuana garden tips in future articles. We highly recommend you experiment with 24-hour lighting during grow phase, so you get faster growth, stronger plants, and more harvests per year.