If you're a grower, you're probably looking into metal halide grow light (a.k.a. MH) to give your garden a healthy, beautiful green lush. But with so many different MH grow lights on the market, it can be hard to know which is the best for your needs. But what is an MH grow light? What spectrum should you use? When should you use it? And how do you choose the best metal halide bulbs and hanging system for your garden? In this article, we'll answer all of those questions and more. So read on to learn everything you know about metal halide grow light!
Overview of the best metal halide grow light:
Best MH Grow Light Bulb
Protopia 600 Watt Metal Halide Grow Light
- Bulb Base: E39
- 600 Watt
- Light Color: Blue
- Light Type: Metal Halide
Best Overall
iPower GLBULBM400 400W Metal Halide Grow Light
- Bulb Base: E39
- 400 Watt
- Light Color: Blue, Red
- Light Type: HPS, Metal Halide
Energy Efficient
iPower GLBULBM600X4 4-Pack 600 Watt Vegetative Metal Halide MH Conversion Grow Light Bulb
- Bulb Base: E39
- 600 Watt
- Light Color: Blue
- Light Type: Metal Halide
What is a metal halide grow light?
A metal halide grow light is a high-intensity discharge (HID) light commonly used in indoor gardening and hydroponic systems. MH grow lights were first developed in the early 20th century and have been a popular choice among indoor growers. Today, MH bulbs are used in various settings, from commercial greenhouses to small home gardens. As technology has improved over the years, MH bulbs have become more efficient and versatile, making them a top choice for growers looking to maximize their plant yields.
What is a metal halide bulb?
A metal halide bulb is a key component of a metal halide grow light. The MH bulb comprises two main parts: an arc tube and a base. The arc tube houses the metal salts used to produce the intense white light, while the base provides electrical connections for the metal halide bulb. These bulbs typically emit a spectrum of light ideal for photosynthesis and plant growth, making them an essential tool for any serious indoor gardener. These lights are often rated with a 100-lumen output per watt, a 20,000-hour lifespan, and moderate degradation rates-making them ideal for garden use.
It is important to take precautions when using MH grow lights, such as using proper safety equipment and handling bulbs cautiously. High heat and burns are potential hazards when using MH grow lights. These lights produce great heat and can easily cause burns if not handled properly.
The spectrum of metal halide grow light
A light spectrum chart is a graphical representation of the different light wavelengths emitted by a light source. This information can be used by growers to choose the best light spectrum for their plants. PAR, or photosynthetically active radiation, is a useful measurement for indoor growers looking to maximize plant growth and yields.
MH bulbs tend to have a PAR spectrum ideal for plant growth, making them a popular choice among growers. The light spectrum for a metal halide grows light is typically in the white-blue range, making it ideal for photosynthesis and plant growth. UV and red light are also emitted by metal halide bulbs, which may benefit certain plants. However, MH grow light has very low output in the red part of the spectrum. This can be a disadvantage for some plants, as they may not receive all of the benefits of red light. Check our article for in-depth grow light spectrum guide.
When should you use a metal halide grow light?
Each type of plant has different light requirements and will thrive under different lighting conditions. Indoor growers have the advantage of being able to tailor their lighting to meet the specific needs of their plants. Typically, MH grow lights are used by indoor gardeners during the vegetative stage of plant growth. MH light bulbs are known for their cool white light and high intensity, making them ideal for helping plants produce strong stems and leaves while they're still small.
Indoor growers using MH grow lights often switch to high-pressure sodium (HPS) lights during the flowering stage of plant growth. HPS lights emit a spectrum of light ideal for flowering and fruiting plants. However, if the gardener prefers, MH bulbs can be used during the flowering stage. MH bulbs are also very good at stopping stretching when a plant grows taller than it should receive more light. If you use an MH bulb during the flowering stage, it is important to keep an eye on your plants to ensure they don't stretch too much.
Best metal halide grow light review
Here is the list of the best metal halide grow light available in the market.
1. Protopia 600 watt metal halide grow light (best metal halide grow light bulb)
Protopia MH600WTT76 600 Watt Metal Halife Grow Light
Features:
- Bulb Base: E39
- 600 Watt
- Light Color: Blue
- Light Type: Metal Halide
2.Ipower 400w metal halide grow light (best overall)
iPower GLBULBM400 400W Metal Halide Grow Light
Features:
- Bulb Base: E39
- 400 Watt
- Light Color: Blue, Red
- Light Type: HPS, Metal Halide
3. Ipower 600 watt vegetative metal halide conversion grow light bulb (energy efficient)
iPower GLBULBM600X4 4-Pack 600 Watt Vegetative Metal Halide MH Conversion Grow Light Bulb
Features:
- Bulb Base: E39
- 600 Watt
- Light Color: Blue
- Light Type: Metal Halide
Choosing your metal halide bulbs
When selecting MH bulbs for your garden, there are a few important factors to keep in mind. These include-
Bulb wattages: Metal halide bulbs are available in various wattages, from 250 watts to 1000 watts. The size and intensity of your MHbulb will depend on the size of your grow space and the type and stage of growth your plants are in. High-wattage MH bulbs can be used for larger gardens or plants in the flowering stage, while lower-wattage bulbs may be more suitable for smaller gardens or plants in the vegetative stage.
Spectrum: Metal halide bulbs emit a cool white light high in blue, violet, and UV light. This light spectrum is ideal for enhancing plant growth during the vegetative stage. However, it may not be suitable for flowering plants and can cause blooming to occur too early. Check our article for in-depth information on plant grow light spectrum.
Color temperature: The color temperature of a metal halide bulb is measured in kelvins, ranging from 3000K to 20,000 K. Larger bulbs emit blue-white light with lower kelvin ratings, while smaller bulbs emit more yellow-white light with higher kelvin ratings. Depending on the stage of growth and type of plant you are growing, you may want to choose an MH bulb with a different kelvin rating.
Download our complete guide to choose the best grow lights for indoor plants
Hanging your metal halide grow light
When hanging your MH grow light, it is important to consider the height and coverage of your bulb. High-wattage MH bulbs should be hung no more than 18 inches above your plants, while lower-wattage bulbs can be hung anywhere from 12 to 24 inches above your plants. Make sure your MH bulb covers the entire canopy of your plants for the best results. Check our article for in-depth knowledge on how far should grow lights be from plants.
In addition to choosing the right wattage and color temperature for your metal halide bulbs, choosing a high-quality bulb designed specifically for indoor growing is also important. Many different brands and models of MH light bulbs are available, so it's important to research to find the best ones for your garden.
When should you use a metal halide grow light?
Overall, there are many benefits to using MH grow lights in your indoor garden. MH grow lights shines when:
- You are growing small, leafy plants in the vegetative stage
- You want to give your plants a boost of blue, violet, and UV light
- Your garden space is limited, and you need more intense light coverage
- You want to avoid the risks associated with using high-pressure sodium (HPS) lights during the flowering stage
- You want to maximize the growth and development of your plants
- You are looking for a cost-effective lighting solution that is easy to install and maintain
Choosing your ballast
The grow light ballast is essential to any metal halide grow light system. The ballast provides power to the bulb and regulates its operation. Ballast types differ in power, efficiency, and control features, so choosing the right ballast for your garden is an important part of setting up your MH grow lights. Check our article for in-depth information on plant grow light ballast.
iPower GLBLST1000D Horticulture 1000 Watt Digital Dimmable Electronic Ballast
Some key considerations to keep in mind when choosing a metal halide grow light ballast include-
Wattage: Metal halide bulbs are available in a range of wattages, so you will need to choose a ballast that is compatible with your bulbs. Ideally, your MH bulb should use about half of the total power rating of your ballast.
Efficiency: The higher the efficiency rating of your ballast, the less energy it will consume and the longer it will last. Look for ballast with an efficiency rating of 90% or higher.
Control features: Many metal halide grow light ballasts offer additional control features to help you customize your lighting setup, such as dimmable controls and protections against power surges. Choose a ballast that offers the control options you need for your garden.
Metal halide vs. HPS
When choosing between metal halide and high-pressure sodium or HPS grow lights, it is important to consider the type of plants you are growing and their growth stage. Here are some key differences between MH and HPS grow lights: Check our article for in-depth information on HPS grow lights.
- MH bulbs emit a blue, violet, and UV light spectrum ideal for leafy plants in the vegetative stage.
- HPS bulbs emit a red and orange light spectrum that promotes flowering in plants.
- MH bulbs are less efficient than HPS bulbs and require more energy.
- MH bulbs typically last longer and are more durable than HPS bulbs, making them a good choice for high-intensity applications.
- Depending on their wattage rating, MH bulbs can be more expensive than comparable HPS bulbs.
Metal halide vs. LED
There are several factors to consider when comparing metal halide and LED grow lights. These include-
Light intensity: Metal halide bulbs use high-wattage bulbs to produce intense light that can penetrate deeper into the canopy of your plants. In contrast, LED bulbs typically have lower wattage ratings and emit a more diffuse light.
Spectrum: Metal halide bulbs produce a blue and UV light spectrum, making them ideal for leafy plants that need more violet and UV light during the vegetative stage. In contrast, LED lights tend to have broader spectrums that include more red and orange light, which is optimal for plants in the flowering stage.
Efficiency: LED grows lights typically have higher efficiency ratings than MH bulbs, making them a more cost-effective choice for large-scale applications.
Lifespan: LED bulbs also last longer than metal halide bulbs, making them a more reliable choice for growers who want long-term lighting solutions.
Ceramic metal halide grow light
Ceramic metal halide (CMH) grow lights are similar to traditional MH bulbs but use ceramic arc tubes and a special amalgam that provides a more consistent light output. This makes CMH grow lights ideal for setting up large-scale indoor growing operations. Some key benefits of using CMH grow lights include the following-
- Consistent light output: The ceramic arc tubes and special amalgam used in CMH bulbs help to maintain consistent light levels, even as the bulb ages. This makes them ideal for commercial growers who need reliable lighting solutions for their plants.
- Energy efficiency: While metal halide bulbs require high-wattage ballasts, CMH bulbs use lower wattage and run cooler, making them a more efficient option for large-scale applications.
- Long lifespan: Due to their ability to maintain consistent light output over time, ceramic metal halide growth lights can last up to 10 times longer than traditional MH bulbs.
Check our article for in-depth information on CMH growl light.
Metal halide vs. ceramic metal halide
When comparing metal halide and ceramic metal halide grow lights, it is important to consider the different types of plants you are growing and their growth stage. Here are some key differences between these two lighting options:
- MH bulbs produce a blue and UV light spectrum ideal for leafy plants in the vegetative stage, while CMH bulbs offer a broader light spectrum with more red and orange wavelengths, which are optimal for plants in the flowering stage.
- MH bulbs require high-wattage ballasts, while CMH lights use lower wattage and run cooler. This makes them a more energy-efficient option for large-scale applications.
- MH bulbs generally have a shorter lifespan than CMH bulbs, making them less reliable for growers needing long-term lighting solutions. When deciding between metal halide and CMH grow lights, you must consider your specific growing needs and the type of plants you are cultivating.
Metal halide grow light kit
A metal halide grow light kit can be great for growers looking to create beautiful, healthy plants. These kits typically include all the essential components needed for installing your metal halide lighting system, including high-wattage bulbs, ballasts, and hanging hardware.
iPower Ceramic Metal Halide Grow Light Kits; High-Reflectivity Aluminum Hood and 120-240V Ballast with Full-Spectrum CMH Hydroponic Lamp System
Some key factors to consider when choosing an MH grow light kit include the following:
Light intensity: MH bulbs produce intense light that can penetrate deep into the canopy of your plants, making them ideal for gardeners looking for high-quality lighting solutions.
Bulb type: Various MH bulbs are available, depending on your growing needs. For example, some bulbs may offer a broader light spectrum with more red and orange wavelengths, which is optimal for plants in the flowering stage.
Size and capacity: MH grow lights come in various sizes to suit different growing applications, from small hobby gardens to large commercial operations. It is important to consider the size of your garden when choosing a metal halide grow light kit, its capacity, and whether it can be easily connected to other components in your lighting system.
Budget: MH grows light kits can vary widely in price, depending on their size and features. When deciding which kit is right for your garden, it is important to consider your budget and look for a kit that offers the best value for your money. With the right metal halide grow light kit, you can create healthy, thriving plants that will provide you with bountiful yields all year round.
100 watt metal halide grow light
A 100-watt metal halide light may be the right choice for you. This type of bulb is designed to produce bright, intense light that can penetrate deep into the canopy of your plants, helping them thrive and produce bountiful yields.
When using a 100W MH bulb, it is important to keep your plants at least 14’’ or 30 cm away from the light to prevent them from burning. Position your light so it hangs at least 18’’ or 46 cm above your plants for the best results. If you have a garden up to 3.5’ x 3.5’ or 1.1m x 1.1m in size, a 100-watt MH grow light will be ideal for providing your plants with the intense light they need to thrive.
150 watt metal halide grow light
With a 150W MH bulb, keeping your plants at least 14’’ or 35 cm away from the light is important to prevent them from burning. To get the best results, hang your light at least 24’’ or 61 cm above your plants and position it to shine directly on them. If you have a garden up to 3.5’ x 5.5’ or 1.1m x 1.7m in size, a 150-watt MH grow light is a great choice for providing your plants with the high-quality lighting they need to thrive and produce bountiful yields.
175 watt metal halide grow light
When using a 175W MH bulb, keeping your plants at least 14’’ or 35 cm away from the light is important to prevent them from burning. To get the best results, hang your light at least 32’’ or 81 cm above your plants and position it to shine directly on them. With a 175W MH bulb, you can create healthy, thriving plants that produce bountiful yields in even the largest gardens.
250 watt metal halide grow light
When using a 250W MH bulb, keeping your plants at least 18’’ or 46 cm away from the light is important to prevent them from burning. To get the best results, hang your light at least 48’’ or 122 cm above your plants and position it to shine directly on them. With a 250W MH bulb, you can create robust, healthy plants that produce massive yields in even the largest gardens.
400 watt metal halide grow light
When using a 400W MH bulb, keeping your plants at least 18’’ or 46 cm away from the light is important to prevent them from burning. To get the best results, hang your light at least 60’’ or 153 cm above your plants and position it to shine directly on them. With a 400W MH bulb, you can create large, robust plants that produce massive yields in even the largest gardens.
iPower GLBULBM400 400W Metal Halide Grow Light
600 watt metal halide grow light
It is important to keep your plants at least 24’’ or 61 cm away from the light when using this type of light to prevent them from burning. To get the best results, hang your light at least 84’’ or 213 cm above your plants and position it to shine directly on them. With a 600W MH bulb, you can create massive, robust plants that produce abundant yields in even the largest gardens.
Protopia MH600WTT76 600 Watt Metal Halife Grow Light
1000 watt metal halide grow light
When using 1000W MH bulbs, keeping your plants at least 36’’ or 91 cm away from the light is important to prevent them from burning. To get the best results, hang your light at least 96’’ or 244 cm above your plants and position it to shine directly on them. With a 1000W MH bulb, you can create extremely large, robust plants that produce massive yields, making it the ideal choice for growers with large and/or high-yield gardens.
iPower 1000 Watt Vegetative Metal Halide Lamp
Metal halide grow light fixture
MH grow light fixture is a high-intensity discharge light commonly used by growers to provide their plants with the optimal amount of light and energy for healthy, vigorous growth. This grow light features a specialized spectrum designed to help maximize photosynthesis in plants, resulting in faster growth and bigger yields.
FAQ
What is a metal halide grow light?
A metal halide grow light is a type of high-intensity discharge lighting commonly used by growers to provide their plants with the optimal amount of light and energy for healthy, vigorous growth. These lights feature a specialized spectrum designed to help maximize photosynthesis in plants, resulting in faster growth and larger yields.
What is the spectrum of a metal halide light?
The spectrum of a metal halide light is characterized by high levels of blue and green wavelengths, which help to promote photosynthesis in plants. Additionally, metal halide lights also produce smaller amounts of red and UV wavelengths to support other aspects of plant growth and development.
When should you use a metal halide grow light?
There are many different factors to consider when deciding whether to use a metal halide grow light, such as the size and type of your garden, the stage of plant growth, and your specific growth goals. In general, metal halide lights are well-suited for growers with high levels of photosynthetic energy for fast growth or large, high-yield gardens. Additionally, these lights are typically best used during the vegetative stage of plant growth.
How do you choose metal halide bulbs for your grow light?
There are several factors to consider when choosing metal halide bulbs for your grow light, such as the wattage and type of bulb, as well as the size and layout of your garden. Generally, it is recommended to start with a lower-wattage bulb, and then increase the wattage if needed to support plant growth or achieve higher yields. Additionally, you should carefully consider the height you are hanging your light and position it so that it shines directly on your plants without burning them.
When should you use a metal halide grow light?
There are many factors to consider when deciding whether to use a metal halide grow light, such as the size and type of your garden, the stage of plant growth, and your specific growth goals. In general, metal halide lights are well-suited for growers with high levels of photosynthetic energy for fast growth or large, high-yield gardens. Additionally, these lights are typically best used during the vegetative stage of plant growth. To choose the right metal halide bulbs for grow light, you should consider the wattage, type of bulb, and size and layout of your garden. It is recommended to start with a lower wattage bulb, and then increase the wattage if needed to support plant growth or achieve higher yields. Additionally, you should carefully consider the height you are hanging your light and position it so that it shines directly on your plants without burning them.
How do you hang a metal halide grow light?
There are several factors to consider when hanging a metal halide grow light, including the size and layout of your garden and the height at which you want to position your light. In general, it is recommended to mount your metal halide light high enough above plants so that the light can shine directly on them without burning or overheating them. Additionally, it is important to ensure that the light is properly positioned to shine directly on your plants rather than off to the side or at an angle. Finally, you may consider using a reflective material or setup to help direct more light onto your plants and increase their exposure.
What are some key differences between metal halide and other grow lights, such as HPS or LED?
Some key differences between metal halide and other grow lights include their light spectrums, efficiency, and cost. Metal halide lights are typically characterized by high levels of blue and green wavelengths, which support photosynthesis in plants. In contrast, HPS lights are known for their high levels of red wavelengths, which support flowering and fruiting in plants.
How many watts should a metal halide bulb be for my garden size?
There is no definitive answer to this question, as many factors can influence the optimal wattage for your metal halide bulb. Some of these factors include the size and layout of your garden, your specific growth goals, and your lighting needs. Generally, starting with a lower-wattage bulb and then increasing the wattage if necessary to support plant growth or achieve higher yields is recommended. Additionally, you should carefully consider the height you are hanging your light and position it so that it shines directly on your plants without burning them. Ultimately, the optimal wattage for your metal halide bulb will depend on various factors, so it is best to consult with a trusted grow light expert or other experienced growers before making your final decision.
Which plants are best suited for metal halide grow lights?
There is no definitive answer to this question, as different plants may have different light requirements depending on their growth stage and individual needs. However, in general, metal halide grow lights tend to be most effective for supporting fast-growing plants requiring high photosynthetic energy levels. Some common examples of plants that may thrive under metal halide grow lights include leafy greens, herbs, and fruiting plants like tomatoes. To choose the right metal halide bulbs for your garden, it is best to consult with a trusted grow light expert or other experienced growers to assess your specific plant needs and find the optimal setup for your garden.
Metal halide vs. HPS
When comparing MH and HPS grow lights, it is important to consider the unique qualities of each type of bulb. Some key differences between these two lighting options include the following:
- MH bulbs produce a blue and UV light spectrum ideal for leafy plants in the vegetative growth stage, while HPS bulbs emit more red and orange wavelengths, which are optimal for flowering plants.
- While both bulbs typically require high-wattage ballasts, HPS grow lights use more energy and run hotter than MH bulbs.
- MH bulbs generally have a shorter lifespan than HPS bulbs and may need to be replaced more frequently. However, this also means they are often less expensive than HPS bulbs.
When choosing between MH and high-pressure sodium grow lights, you must consider your specific growing needs and the type of plants you are cultivating. Whether you choose, MH or HPS bulbs will depend on whether you are growing leafy or flowering plants and their growth stage. With the right setup and care, either type of bulb can help you yield healthy, vibrant plants.
Learn everything about hydroponics, from the basics to advanced techniques.
