December 16, 2021
When growing plants under HID grow lights like MH or HPS, you want to take as much light from the bulb as possible and deliver it directly to your plants. This is important because maintaining strong light levels in the flowering stage is the only way to grow dense buds and get brag-worthy yields. Higher light levels (up to a point) are also associated with increased potency.
By using a reflector (especially when combined with reflective walls), you can get a significant amount of extra light to your plants without using any more electricity, resulting in faster growth and bigger harvests.
The hood / reflector focuses light down, increasing light levels experienced by the plants
Example of an HPS grow light setup up with an air-cooled hood, ducting and and exhaust system
But which reflector is best for your grow light and space? Is it worth it for you to get a better or more expensive reflector than what you have now, or will your results end up being about the same? Keep reading!
If you’re new to indoor gardening, the first question that comes to mind may be: What is a grow light reflector, and why should I care about them?
As it turns out, reflectors are an essential part of any grow light. They’re basically shields made of a reflective material — typically smooth or textured aluminum.
Grow light reflectors play a vital role in getting your plants all the light they need to thrive by doing a couple different tasks, which we’ll discuss now.
Reflectors Power Your Grow Lights: To start, without a reflector, your grow bulb wouldn’t light at all. Reflectors help transfer the power they receive from the light’s ballast into the bulb — the bulb then uses that energy to create an electric arc that heats the filament and produces light.
Reflectors Distribute Light: Reflectors intensify, concentrate, and direct the light produced by your grow bulb onto the plants below it. Without a reflector to distribute light, the bulb would simply shine into the open air and the light would bounce onto the ceiling and walls around it. This would reduce the light’s effectiveness and lead to much wasted energy and light that isn’t getting to the plants that need it. A reflector ensures proper, intense coverage.
Single-Ended and Double-Ended Reflectors
The first distinction to make between the different types of grow light reflectors is that some of them are designed for single-ended grow lights and others are made for double-ended grow lights.
There are two varieties that HPS grow lights come in:
Single-ended reflectors have sockets that Edison-style single-ended bulbs are screwed into.
Double-ended reflectors are designed so that double-ended grow lights, which have two ends, can snap into place.
The type of HPS grow light you’re using will determine the type of reflector you need. Remember: A double-ended grow light will not be compatible with a single-ended reflector and vice versa.
Sun System Agrotech® Magnum Reflector
Features:
The unique double-ended construction of this Sun System reflector allows for maximum optical efficiency and uniformity. Improved spectrum DE lamps used in this fixture focus on the red component for increased photosynthetic response. They offer improved PAR values and increased PAR/lumen maintenance (up to 90% PAR at 10,000 hrs of operation). 95% reflective textured German aluminum for excellent reflectivity, output and diffusion. Oversized design is excellent for larger growing areas and closer placement to plant canopy. What’s great about this reflector is that it is so wide, it covers the long edges of the area very well. Instead of positioning the reflectors in the center of each 4' x 4' square we recommend that you push them away from each other, so that they are almost at the edges of the 8' area. This is due to the fact that the DE lamp produces so much plant-usable light that instead the “hot spot” forming underneath the lamps, it actually forms directly between the two reflectors.
Features:
The Silverstar CMH reflector is made from highly reflective German textured aluminium for excellent light uniformity and diffusion. It has a multifaceted design that will provide superior uniformity and maximum output. The Silverstar CMH 315W has an integrated PGZX socket that is designed for use with CMH technology. Renown for its quality, Silverstar is always a sure investment. The Silverstar 315W System provides maximum lumen intensity, uniform distribution, and deep canopy penetration. The vertically installed CMH bulb (not included) provides an efficient and complete spectrum, with higher efficiency and less heat output when compared to HPS or MH lamps. Since the CMH bulb spectrum is much wider than HPS/MH, a 4200K or 3100K bulb can be used from vegetative state straight through to flowering, or alternate 4200K during vegetative and 3100K for flowering to maximize growth and yield.
Get Most Reflective Hood as Possible (95% Reflectivity)
Hoods commonly come labeled as having 85% or 95% reflectivity (though some may not say anything about reflectivity, which usually means it’s 85%). Although it’s often more expensive to purchase a hood with higher reflectivity, it’s not a bad idea if you can afford it! Although there’s not a huge difference in performance between the two types, the 95% reflective hoods definitely do reflect more light. Every bit of extra light received by your plants can make a difference!
Get a reflector / hood that is labeled to have 95% reflectivity, if possible
A Good Hood Can Be Opened Up
This may be something you don’t think about the first time you’re getting a hood/reflector, but they each have different ways to get inside so you can screw in your bulb.
If possible, get a hood that’s been labeled as having either “hinges” or “sliding glass” (preferably hinged) in order to get to the light socket. Otherwise you might be sticking your hands in from the side air hole whenever you want to change the bulb. Not being able to get past the glass can also make it difficult to clean the inside of your hood if it gets dirty (and the glass should be as clean as possible to make sure it’s not blocking any light from getting through). However, although this is a matter of convenience for you, it doesn’t really have much effect on your plants.
Make sure you can somehow remove or open the glass in order to get to the inside of the air-cooled hood to change the bulb or clean the glass
Do I want a 6-inch or 8-inch opening on the sides?
Every air-cooled hood has an opening that can be used to connect the hood to a fan or ducting. These openings come in different sizes, so which do you choose? 6-inch is the most common size, and has the most options, but you may have reasons to want a bigger size.
6-inch — Effective for cooling up to three lights that are hooked together < — Most common sieze, if you’re not sure, get this!
8-inch — Necessary to get enough airflow when more than three lights are being hooked together, though you have fewer options
Make sure your hood has the right sized openings for the ducting you plan to use (if in doubt, get one with 6-inch openings)
Remember that it’s usually best to go with a cooled reflector when possible, especially if you’re worried about grow room temperatures rising too much.
Overall, though, once you know what you need for your grow room, making the right choice is a lot easier! When in doubt, just check out our suggestions above, and know that there’s no wrong way to go with any of the options listed in this guide.
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When choosing Best LED Grow Lights, you should also consider the durability of the lamp, energy efficiency and whether it can meet the light needs of specific plants. For example, the LED plant growth lights provided by Philips Lighting are designed for specific crops to promote uniform growth and improve quality and yield.
June 20, 2024
June 15, 2024
On Amazon, hot growth light types include LED Growing Lights, which have a variety of functions and features such as automatic on/off timing, red and blue LED light combinations, multiple dimmable modes, and flexibility for indoor potted plants or indoor gardens.