I’m going to teach you some basics so pay attention, there will be a test on this later on. Plants absorb light along with carbon dioxide, converting the light energy to chemical energy through a process called photosynthesis. The plant grow lights spectrum type, duration, and intensity all play key roles in vegetative, flowering and overall plant health.
The Perfect Intensity
When you are doing it right, plant grow lights provide adequate light, so plants continue along their life cycle as nature (the grower) intended. When too little light is available, plants will grow tall, elongated stems because the plant is stretching to find additional energy rather than producing leaves to harness the available light.
The problems with stretching is two fold. First it makes your plant tall and thin which can be a problem if the you are growing in doesn’t have enough height to accommodate your plant. Second is it will significantly lower your plants yield because the plants energy was wasted on growing tall instead of producing more buds.
A lot of stretching isn’t gonna work for your indoor plants. You can’t just put any old 1000 watt plant grow light over your plants and call it good, a careful balance must be made between the amount, type, and duration of light produced.
Duration is the Key
What a lot of people don’t know is cannabis plants perform a portion of their growth during the dark hours so it’s best not to have light all 24 hours. 18-20 hours of light is recommended. As you probably already know, shortening the duration of a light will trigger flowering. It’s recommended that an equal balance between light and dark (12 hours of light, 12 hours of complete darkness), be maintained during the flowering phase for best results.
When it comes to indoor plants, even just a few hours under a LED light will produce the best houseplants. By providing additional red and blue spectrum light produced by plant grow lights, you are giving your plant what it needs to thrive.
If you want your house plants (not marijuana) to grow to their full potential its best if you provide a full day of light from your chosen source. This can be achieved best with LED, followed by MH/HPS, then Fluorescent as far as performance goes.
Be sure to research your plant’s requirements when setting the height of your LED light(s). Too close (within inches) will cause your leaves to burn. It’s best to maintain 18 inches of distance or more depending on the power of your light or whether it has secondary optics which focus the light directly vertical of the light.
I prefer to keep my lights a couple feet or more over my younger plants because it encourages the plants to grow in height and when they reach the desired height, that’s where the light will remain. In fact, the healthiest houseplants I have are LED grown.
Fluorescent plant grow lights produce a cool blue light and are low heat and can be set very close to the tops or canopy of plants which make them a good choice for seedlings. Fluorescents are fairly cheap and come in a variety of styles and sizes though most commonly sizes used are T5, T8, and T12.
Pros: Inexpensive, cost-efficient, long service life, low heat production, and ideal for the seedling stage of growth.
Cons: Produces a narrow spectrum of cool light that poorly promotes a flowering response in plants, contains hazardous materials.
Metal Halide (MH)
MH plant grow lights produce cool light in the range of 2700 to 5500 Kelvin and very closely mimics natural light. This makes it an obvious choice for promoting vegetative growth. Excessive heat produced requiring fans for cooling the surrounding atmosphere.
Pros: Very close to natural sunlight spectrum & effective during the vegetative growth stage.
Cons: Uses a lot of power, require high frequency ballasts, can be expensive, excessive heat, and a short lifespan.
High-Pressure Sodium (HPS)
HPS plant Grow lights produce light in the red end of the spectrum which is a reproductive trigger in plants. These lights are often used during the flowering cycle and work considerably well but they produce excessive heat which generally requires fans for cooling the surrounding atmosphere.
Pros: Great flower production during bloom phase.
Cons: Grows taller, thin plants, causes discoloration in leaves, produces a lot of heat, somewhat expensive, requires high frequency ballasts, short lifespan.
Light Emitting Diodes (LED)
LED plant grow lights are the present and future of indoor home and industrial growing operations. They consist of low-wattage LEDs that are arrayed on a circuit board in many different formations to effectively produce light. LEDs are exceedingly energy efficient and have a very long lifespan (up to 50,000 hours or more).
LED plant grow lights are able to produce Blue (430nm-450nm) and Red (640nm-680nm) spectrum points simultaneously without any other inefficient wavelengths. LED’s do not produce excessive heat like other lights, so you don’t have to use such a big cooling fan for ventilation. Hands down, the best for indoor plants during all phases of development.
Pros: Can produce dual-band color spectrum (red and blue) at the same time as well as full spectrum light, most energy-efficient of all grow lights, generates minimal heat and promotes an overall sense of awesomeness.
Cons: Used to be expensive but recent changes in their manufacturing process has lowered prices tremendously.
Okay, time for the test. Just kidding, there is no test, you made it this far so give yourself credit. But can you see why LED’s are the best plant grow lights? Heat, poor efficiency, sub-standard color spectrum, even more heat (Because MH & HPS get HOT!), short lifespan, etc., those are things you don’t need to worry about with LED’s.
As you can probably tell, I am a big fan of LED grow lights, and my experience says they are the best. But what do you think? I’d love to hear your thoughts or if you have any questions please let me know in the comment section below.