Stages of Growing and Light Usage

What kind of lights do I need to grow marijuana?

Choosing grow lights is essential for any weed grow room design. As far as indoor cannabis cultivation goes, there is a vegetative stage (which is usually a couple of weeks) and a flowering stage (which can usually range from 8 to 9 weeks). Cannabis plants in veg stage will want grow lights that emit Just remember when it comes to your grow lights, the blue spectrum is used for veg and red spectrum for flowering.


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What are the growing stages of the cannabis plant?

The stages go like this.

Vegetative Stage and Flowering Stage

Stage one. Vegetative Stage (A)
, 18 hours of light. When a cannabis seed is first planted or you start with clones, your cannabis plants will enter a vegetative stage where it begins to grow out its stems to prepare for budding and the flowering stage. For indoor pot growing, the vegetative stage for cannabis can last anywhere from 1 week to about 40 days and requires a standard day light cycle of 18 hours on. Some growers prefer a 24 hour light cycle for the vegetative stage, which will stimulate quicker and faster growth. Either one should work fine, however, a standard day light cycle may work better for most cannabis strains. The best bulb for the cannabis vegetative stage would be a compact florescent light, CFL, or Metal Hallide, MH, bulbs.

When we “flip  the lights”, our cannabis plants enter stage two. Flowering Stage (B), 
12 hours of light. After 40 days or a couple weeks (whenever you want to end the vegetative stage) the light cycle needs to switch to 12 hours on – 12 hours off in order to start the cannabis bud flowering stage. Flowering starts as soon as you switch the light cycle to 12 hours allowing the cannabis plant to produce buds to smoke later. A cannabis grower flips the lights to enter flowering stage. This is based on good judgment based on plant size and the size of the pot grow room. For maximum growth, some weed growers allow their pot plants to veg for up to 40 days or so to grow the pot plant nice and big before budding. For the cannabis flowering stage, a grower will want to use high pressure sodium, HPS, bulbs. HPS lights generally come in 400, 600, 1000 watt ratings and may need a ballast and a lighting controller to power them. The grow lights used for flowering cannabis plants usually eat up more electricity than the CFLs or Metal Hallide grow bulbs.


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Red versus blue when growing marijuana

Cannabis plants use all colors of the spectrum but generally blue light spectrum is used by the plant for the veg phase and red light is for flowering your pot plants. Lumens and PAR (Photosynthically Active Radiation) are different ways to measure light output from your grow lights. Depending on the grow bulbs you will be using, too much energy consumption in either phase, can draw suspicion from law enforcement agencies as they have been known to secret monitor unusually high energy consumption.

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