Growing marijuana indoors, you need to know the best schedule to set your timer for the Vegetative Light Cycle to come on and turn off. While the marijuana plants are in the vegetative growth stage they require a minimum of 12 hrs per day of light, preferably Metal halide grow lights, which produce the white/blue color light spectrums plants crave to grow healthy. There are growers that use 18hr or 24hr light cycles as these 2 are the most common ways of growing indoor marijuana plants. I will explain the most common light cycle and the more advanced, energy saving method I use to grow healthy mother plants.

24 Hour Light Cycle for Marijuana

The 24 hour light cycle is by far the most common way of growing cannabis plants indoors, in the vegetative, clone or mother plant stages. You don’t even need a timer for this as the lights remain on 24 hours a day, never needing to be turned off. You can also set a timer to come on for 18 hours and off for 6 hours, which is also considered a “24hr cycle option”. By doing this, you are wasting electricity, and burning through bulbs much faster than you should be, all costing you more time and money that you shouldn’t have to worry about. The 24 grow light cycle will cause the mother plants and clones to grow at such a fast rate that it may become a problem with space and light.

Advanced Marijuana Growing Light Cycle

The advanced light cycle for marijuana growing will save you time and money, allowing for more quality plants and marijuana buds. This grow light cycle will also save wear and tear on your Metal Halide or Grow Bulbs you are using. Here is a schedule to follow for an advanced growers vegetative light cycle:

Lights used in the Vegetative Growth Stage

This light cycle is 13 hours on and 11 hours off each and every day. Simply set your digital timer to come on for 12 hours, off for 5.5 hours, on again for 1 hour, then off for 5.5 hours.

By doing this you will give the marijuana plant enough light per day for it to continue growing in the vegetative stage, as well you are saving close to 50% in your electricity bill. This vegetative light cycle is highly used by all of my veteran medical marijuana growers.

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