Grow Room Lighting

Indoor gardening requires some form of artificial lighting in place of sunlight. Plant grow lights come in many shapes and sizes. The GYOstuff Grow Light Guide is a great way to find the right light for your garden. This guide is based on high-quality components like those found at GYOstuff.




High Intensity Discharge (HID) lighting is the most effective type of lighting available for your indoor garden. As these lights are very bright and intense, they produce excellent usable light for your plants. High intensity bulbs come in a variety of color spectrums. Generally blue spectrum light is used during the vegetative growth cycle for both flowering and non-flowering plants. Bulbs that produce a blue spectrum are Metal Halide (MH) with a 6K color temperature. Red spectrum light is generally used during flowering. High Pressure Sodium (HPS) bulbs produce a red spectrum light with a color temperature of 3K used during flowering. For optimal penetration during flowering, the rule-of-thumb is 40-50 watts per square foot.

HID lighting can get hot - especially at higher wattages. If heat is going to be a concern, you should consider using an air-coolable reflector along with an in-line exhaust fan and air duct to capture the heat from the bulb and take it out of the garden. We also offer heat shields for some of our reflectors to help capture all of the heat from your HID setup.

Always - this can’t be stressed enough - wipe your bulb down with rubbing alcohol thoroughly after any time you touch it and/or before your fire it up for the first time. The oil in your skin from your finger can cause the glass of the bulb to heat up more at that spot and it could potentially shatter. If not, it will dramatically reduce the life of your bulb. Also make sure the bulb is completely dry before ignition.

Fluorescent lighting runs cooler than HID which allows the bulb to be very close to the plants. However, fluorescent grow lights do not have the intensity of HID lighting and may not penetrate the plant’s canopy adequately. For that reason, fluorescent grow lights are most suitable during seed starting, cloning, early vegetative stages and for plants with low light requirements. Fluorescent grow lights are available with a vegetative or flowering spectrum.

LED lighting is cooler than HID and fluorescent and much more energy efficient. However, most older LED's use 1 watt diodes. 1 watt diodes do not emit sufficient lighting for plants that have a thick canopy of leaves. For that reason, LED lighting is popular for less-leafy plants like smaller kitchen herbs - not tomatoes. With any LED light, it is critical to supplement the LED lighting with "white" light - either compact fluorescent bulbs or HPS.

"Whatever you do, don't get stuck with a dog."

There are LOTS of options when it comes to LED grow lights. At GYOstuff, we've tried and tested most of them and know which LED grow lights to stay away from. Don't be fooled by LED manufacturer's claims that their lights will last forever. While the diodes (bulbs) may have an extremely long life, the other components in the light may not be of such high quality and you'll be stuck with that broken, inferior LED forever. Some manufacturers (including the famous "dog" brand out there) will even force a grower with a defective light to pay for a "technology upgrade" of several hundred dollars when repairing a defective light. When you're investing in LED lighting, don't get stuck with a dog.

We prefer the SolarFlare and Solar Storm LED's.


Magnetic Induction lighting is very intense, uses only a fraction of the electricity that their HID counterparts do - while operating up to 80% cooler! The other huge benefit to magnetic induction lighting is that the lamps last about 100,000 hours. That's about 22 years on a 12/12 lighting schedule. Check out our favorite: The Anubis 800W Dual Lamp Magnetic Induction Grow Light.

LEC (Light Emitting Ceramic) lighting is new to the grow scene but is rapidly gaining popularity due to the amazing full spectrum that is unmatched by other types of HID and LED lighting. Want to know how Light Emitting Ceramic compares to other popular lights like the Black Dog? Click here for the complete report so you don't get stuck with a dog.

Green lighting is often used because it allows you to work in your grow room at night (during lights-off) without disturbing the plants' photoperiod.


Proper Placement & Lighting Changes
Plants do not benefit from light that is not directly aimed on them, so it is important to place your lights correctly for your plants to grow. When starting with seedlings, fluorescent and LED lights can be hung directly over them, about 2-4 inches above the top of the plant. The lights can be moved up as the plants grow to maintain the same distance between the light and the plant. View our selection of light stands and reflector hanging systems.

If you plan on using the MH or HPS right away, start with the light about 20 inches or more above the top of the plants and lower the light an inch or so daily until you think the height is right. If it’s too close, the plants will dry and turn brown. If it’s too far, the plants will grow too tall as they stretch to get closer to their light source.

You can also start the vegetative phase with a fluorescent or LED light turned on for 18 to 24 hours a day for the first one or two weeks or longer. You can use a standard fluorescent fixture (with two) 40 watt bulbs placed about 2 to 8 inches above the tops of the plants. 3 to 5 inches is ideal, but you might have to raise the light a bit higher so all the plants get some light, depending on your setup.

The reason for starting off with fluorescent or LED lighting is to not give the plants too much light at the beginning of the growing process. Let them build up to it as they would in nature where the seeds would germinate in spring when the sun is not as strong as it will be in summer.

The longer a plant has been growing in the vegetative phase, the quicker it will flower. You can force your plants to flower by adjusting the photo period to 12 hours of light per day.

The flowering area would use a standard hydroponic set up with HPS and/or MH fixtures turned on for 12 hours a day. View our selection of lighting timers and controllers.

HID lighting during veg and flowering
Try to keep the MH or HPS light about 12 or more inches above the tops of the plants. If the parts of the plants closest to the light dry-out, raise the light, they are too close. If the plants are too far from the light they will stretch and be tall but produce less fruit - a waste of space. Start high and lower the light an inch or two daily until you think the height is right. Adjustable light hangers are key!

Helpful tip: HID and LED lighting produce colors that make seeing your plants in their natural colors a bit difficult. To view your plants in their natural color under HID and LED lighting (and to protect your eyes), we recommend using grow room glasses

Kelvin color selection guide

3K Lamps: Recommend for the majority of flowering when growing annual plants.

4K Lamps: This is a Full Spectrum light good for all stages of growth.

6.4K Lamps: Popularly used for vegetative growth.

10K Lamps: Use during the last 1-2 weeks of flowering to allow better ripening and finishing.


Light Movers
In order to get the most out of your grow light, it should be installed on a light mover. Light movers eliminate hot spots below reflectors, reduce shadows and increase coverage area by up to 30%. That's significant - especially because lighting is the most expensive part of the indoor garden. What's even better is all this means an increased yield.

We prefer the durability and quiet, dependable operation of LightRail Light Movers. For large-scale and commercial gardeners wanting to move up to 9 lights at the same time on 1 system, check out the LightRail 5.0 Commercial Light Mover Kit.


Want to be sure you set up the best growing environment? Take the 1 hour Grow Op Setup class or check out the other topics in the GYOstuff Learning Center.
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