Q&A with Jorge
Cut the Light
After you grow your seedlings and put them in bigger pots and start the vegetative stage with 18 hours of light, how long do you let plants grow until you cut the light to 12 hours? Or do you shorten the hours little by little?
Abby H., Internet
The number of plants under a light and the height they are at flower induction depends on your desires. Let’s use a single 600w HP sodium hanging over a square meter for our example. You can grow in small 5-liter pots and stuff in 36-48 plants below the lamp. If you are growing with this method plants should be induced to flower with the 12/12-hour day/night photo period when they are less than 6 inches tall. This way the plants will shoot up anotherv30-45 cm before harvest. The light is able to penetrate to the bottom of the plants easily. But, if getting arrested with more plants is of concern to you, you may want to grow fewer bigger plants and achieve the same harvest. Many growers have changed from the “sea of green” technique that requires growing many small plants, to growing no more than 18 plants under a 400 or 600w lamp. When this regimen is used, plants are grown 1-2 weeks before inducing flowering. Plants are 18-24 inches tall when induced to flower with the 12/12 day/night photo period. Some plants shoot up more than a foot when flowering. The most notable are the skunk varieties. You may need to experiment to find the exact best size of specific varieties for growing the heaviest harvest. I suggest that you check with specific seed companies that produce seed you are growing for more exact guidelines.