Lighting and its importance in cannabis growth

Photosynthesis transforms light energy into the chemical energy needed for plant growth. Different light sources produce different colors with varying wavelengths and energy.

Cannabis cultivation has specific lighting requirements. To get the best yield from the marijuana plant, appropriate lighting instructions must be followed.

Some waves of colored lighting are stronger than others. Sunlight contains all colors. When growing indoors, maintenance of regular colored light enhance the growth process and improve yields.

Intensity determines how much light the plant can absorb. Light sources with less intensity tend to produce lengthy and thin plants as they seek more light. High intensity light grows a fuller and a high yield crop.

The vegetative stage of the cannabis’ life needs more light than the flowering stage. It is recommended to use timers for indoor growth to keep the plants on the proper lighting schedule.

When the marijuana has germinated and grown as seedlings, entering the vegetative stage can last seven to thirty days. The more light used, the better the product. Some strains of weed thrive well with a variety of light cycles. This is one reason why regular continuous care must be provided for a successful and better tasting product. While in the vegetative stage, the stems prepare for the pre-flowering and flowering stages.

When the vegetative stage is completed, the lighting to start flowering is scrupulously controlled. The plants form buds with equal light and dark times to start the flowering stage. In this stage, good judgment must be used in applying useful light/dark exposure based on a number of factors.


When the vegetative stage ends and the flowering stage begin, different strains and plant conditions may unevenly applied by newer growers. If the strains are known, monitoring the plants for proper height and development should be followed closely.

When growing indoors, the vegetative stage dark/light schedule is best maintained with fluorescent bulbs which provide nourishment with proper light absorption. Blue color fluorescent light is commonly and successfully used for indoor growing twelve hours on and twelve hours in darkness. Metal halide and high pressure sodium lights may be required in certain circumstances but need quite a bit of energy and may produce an unhealthy amount of heat. To decrease the energy and heat needed for growth, the use of LED light is recommended.

Fluorescent lights carry with them a wide variety of characteristics and spectrum of colors. However, because of their decreased intensity, resulting buds may be small and fluffy. Many of these light bulbs could be necessary to grow certain strains of cannabis and some can increase the use of electricity effectively negating the income of the grower.

LED lights are becoming more useful with their energy efficiency, cool temperature, no need for other equipment, and their wide spectrum of colors. These bulbs are less intense than others and sometimes result in small and thinner plants. Used in conjunction with a supportive light source, LED lights may produce smaller, more-concentrated buds.

High intensity discharge bulbs, high pressure sodium (HPS), and metal halide (MH) are favorites of more experienced growers resulting in larger and thicker buds. However, these bulbs tend to overheat the plants increasing the need for the expense of proper ventilation for temperature control. They may also require each other, specialized fixtures, electric current mediation, the stated ventilation structure, and temperature control.

T5 grow lights are easily used as grow lights. These lights are used to grow many varieties of plant life. They are sold in common hardware and home improvement stores. Though they come in a panel, they can be placed very close to the plants without burning them.

Fluorescent lights are normally used for the early stages of plant development. Some types of supplemental lighting can be used to save money without the use of stronger powered lights for plants too immature to use the energy they provide.

HID grow lights have proven to be more efficient that fluorescents. They are mounted to provide the best light to the plants. However, they are hot requiring the use of a properly installed ventilation system which could increase energy costs.

Metal halide (MH) lights are typically used for the vegetative stage as they produce the needed blue energy for plants until they are harvested.

High pressure sodium (HPS) lights are mostly used during the flowering stage as their yellow light tends to stimulate bud yield. When used in this stage, they are very energy efficient.

Ceramic metal halide (CMH) and light emitting ceramic (LEC) bulbs are very similar to each other. These lights are more cost effective than CMH bulbs but not as effective as HPS light bulbs.

MH/HPS bulbs are larger than other light sources but beyond the cost and care able to be performed by younger growers. These bulbs need a ventilation system and a system for cooling when appropriate. However, a time-consuming amount of setup is required with these bulbs.

1 review

  1. Hermosa Beach Marketing, August 10, 2017 12:57 pm - Lighting and its importance in cannabis growth

    I bet you make babies smile. I am really impressed with your writing skills as well as with the layout on your blog.

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