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The best HPS grow lights are the backbone of the cannabis industry. These ubiquitous bulbs power many marijuana operations – and for a good reason.
Although there are a large number of alternatives when it comes to lighting, nothing comes close to the intensity and growth potential that emits from an HPS bulb. With their time tested results, HPS grow lights remain the best grow lights in the industry.
Join us as we dive into everything related to HPS grow lights, what you should look for before buying, and lastly, our top choices. Once you’ve completed this in-depth guide, you’ll never look at HPS lights the same.
What more can you ask for when purchasing a 600w HID system? The iPower 600w HID offers everything you’ll need to power your plants from seed to harvest. This dimmable system is perfect for beginners to experts, and it couldn’t be any easier to use.
The ballast runs quietly, and you can dim the power output from 100% to 75% and 50%. This increases its versatility, which is always useful when growing cannabis.
All-in-one system that allows you to begin growing immediately
Excellent dimmer with a variety of options
A long-lasting bulb with a rare instance of failure
Ideal cable lengths make sure easy setup
Built from high-quality materials
Poor packaging practice for shipment
Requires additional user-setup
Vivosun is a lighting and hydroponic company that’s dominated the marijuana industry for years. Their products are always well built, and the Vivosun 1,000w HID system is no
exception. They use robust materials, and you can count on this system lasting you many harvests.
As a bonus, the hood is an air-cooled reflector. This makes your growing experience even better by allowing the heat from the bulb to dissipate easily. The wiring is top notch for the
most part, but manufacturer error does occur – so it’s important to look over your system to ensure everything is properly assembled.
Ballast doesn’t hum and comes with rubber feet to prevent vibration
Made from high-quality materials and professional finished
Excellent customer service
Comes with all the parts needed to begin growing immediately
Ideal color spectrum for growing cannabis
The bulbs have a tendency to burn out after a few months of use
The internal wiring could be much better
Ballast runs warm
The Sun System 400w HID grow light is perfect for the small grower. We all have our reasons for growing in smaller spaces, and it doesn’t make you any less of a cultivator. This 400w HD will push your plants to their limit, and you’ll soon be showered with resin covered buds after your hard-earned efforts.
The Sun System 400w HID complete system comes with it all, and this means you’ll spend less time setting it up and more time growing. Be aware that this model doesn’t have a dimming option, but at 400-watts, this shouldn’t be that large of an issue.
Excellent 2-year warranty
Contain your entire HPS system under one roof
Long lasting 400w HPS bulbs
No dimming option
Damage during shipping is an issue with this brand
The High Yield Lighting FloraLux 150-watt HPS system is the standard when it comes to closet-sized grows. This small-but-strong light will pump out the necessary red/orange
wavelength to build those trichome covered buds.
It’s lightweight and professionally built, which makes it a no-brainer when searching for your new closet grow light. It doesn’t hum endlessly like many other models, which makes the High Yield Lighting FloraLux 150-watt HPS system perfect for those that require discretion.
Perfect for micro-scale grows
Doesn’t run warm
Easy to use and setup
Low power rating
The SPL Horticulture 1,000w LED grow light might just be the perfect light available. It’s one of the most value-added products to date due to its 4-bulb package. MH and HPS bulbs are expensive, and it’s recommended that you replace your bulbs after two harvest cycles. This makes the 4 bulb bonus a life-saver for your wallet.
The SPL 1,000w LED grow light also offers the necessary accessories to begin growing immediately. The dimming switch converts this 1,000w beast into an efficient 500w HID in
the flip of a switch. Growing can’t get any easier, especially when you have a tried-and-trusted company behind you, such as SPL.
Excellent shipping service
Contains everything you need to begin growing
High-quality light bulb
Dimmable and air-cooled
Incredible value with 4 1,000w HPS or MH bulbs
Expensive compared to competitors
As you’re walking briskly down a street during the evening, have you ever watched the street lamps turn on? Although these are roughly 20-feet above you, the light is an intense reddish/orange that cascades down across the avenue.
These are high-pressure sodium bulbs, and like metal halide, they are commonly found throughout cities across the world for public lighting.
Now that you know this, the answer is no, you shouldn’t try to place a cannabis plant nearby for free light.
Now that we’re past that, how do these invaluable lights work? First, you’ll need to understand what they’re composed of. To simplify this process, we’ll list the main components that are worth noting.
Most HPS grow lights start with a pulse ignition that’s fired from the ballast. The ignition initializes the HPS bulb by emitting a white color. This is the Xenon heating up first. The second gas the react is the mercury, which emits a bluish light. Lastly, the sodium reacts, and the orange/red hue is then observed.
Aside from lumens and wattage, the color spectrum that’s found in an HPS bulb is the most important factor when growing cannabis. Interestingly enough, marijuana plants respond exceptionally well to the reddish/orange range that HPS lights are known for.
A major question for researchers has been, “why do marijuana plants respond to the red/orange wavelength?”
To answer this, we’ll need to give you some background information on Cannabis sativa/indica. Marijuana is an annual plant, which means that it completes a full life cycle within a year. Typically, cannabis strains begin their life during the late spring after any danger of frost has passed.
Naturally, cannabis plants are in their vegetative stage during peak summer months. The Sun is high in the sky, and this produces a bright white/blue wavelength that only plants recognize. Once the sun begins to set earlier as Fall arrives, cannabis plants understand that it’s time to reproduce to ensure that the next generation is created before the harsh winter months.
This response is a form of phototropism, in which cannabis plants stop leaf growth, but rather, focus on flower production. Female flowers are then pollinated by male flowers, and soon after, cannabis seeds are produced.
As we all know, cannabis cultivators go through great lengths to keep males out of their flowering rooms so as not to pollinate their prized females. The result after many weeks is dense and resinous cannabis buds.
So how does this relate to an HPS bulb? HPS bulbs emit a specific wavelength that resembles winter daylight hours (short days). This stimulates the cannabis plant to switch over from vegetation to flowering. Many studies have shown that HPS outproduces metal halide bulbs because the red and orange wavelength effectively mimic the Sun.
When you turn on your HPS bulb, it contains a high amount of energy depending on its’ wattage. It would be incredibly dangerous if the power being supplied weren’t regulated. This is where an HPS ballast comes into play.
The HPS ballast regulates the amount of power that’s sent over to the arc tube within an HPS bulb. If it weren’t for the ballast, the light wouldn’t be consistent. A ballasts’ job is to maintain a certain amount of power according to its wattage rating.
If a ballast didn’t operate in this way, you’d burn through bulbs every few minutes because they would become overloaded with power. Since HPS bulbs are costly, it would be unfeasible to use them.
Ballasts are also devices that are meant to keep your lights safe. Most new digital ballasts come equipped with automatic shutdown if there’s a power surge. You won’t always be home while your grow lights are in operation, and a ballast that acts as a regulator and as a failsafe device is absolutely necessary.
Many growers are posed with this question when searching for the best HPS grow lights. You can’t consider buying an HPS bulb without thinking about the ballast since these two devices go hand-in-hand.
Magnetic ballasts conduct electricity through the use of copper coils and steel sheets. These materials are heavy, which is why magnetic ballasts weigh far more than digital ballasts.
Magnetic ballasts are also from an older generation. This technology has since been replaced for more user-friendly digital ballasts. This doesn’t mean that they are outdated. Magnetic ballasts are still used by many growers because they’re affordable, easy to fix, and durable.
Magnetic HPS ballasts are tried and true workhorses, which lends the confidence needed to trust your entire grow setup to.
Digital HPS ballasts are technologically advanced compared to magnetic ballasts. Digital ballasts offer dimming options, built-in fans, and remote controlled functionality.
Dimming options are incredibly handy because sometimes you’ll find that you don’t need to use the full 1,000-watts of an HPS bulb. In certain circumstances, it’s more economical to use 50% or 75% of the total power. This is where digital ballasts shine, and having the ability to dim your bulbs by specific percentages offer more flexibility when using a 1,000w, 600w, or 400w HPS bulb.
Aside from the dimming option, digital ballasts are typically lighter in weight compared to magnetic ballasts. This reduced weight helps when installing ballasts inside of your grow space.
Digital ballasts also come equipped with built-in fans to reduce their overall temperature. Magnetic ballasts are far quieter than digital ballasts, but they tend to run much warmer. This onboard fan on digital ballasts offers more peace-of-mind while powering your cannabis operation.
When dealing with lower wattages, such as 150w-400w HPS bulbs, you may find all-in-one systems which can prove to be an invaluable tool in your cannabis garden. These consist of a hood, the bulb, and an attached ballast.
Although these are heavy, they keep all three components within one hood, which is ideal for many small-scale growers. All-in-one systems are also beneficial because they reduce the cost of buying each component separately.
So far, we’ve talked about HPS bulbs and ballasts; next, we’ll discuss the third component that comprises the HPS system: hoods.
Hoods come in all shapes and sizes, and these are efficient tools in spreading light evenly, increasing the overall light output, as well as trapping hot air to be removed via an inline fan.
Hoods are engineered to spread the light your HPS bulbs emit efficiently. These allow the light to be funneled into specific directions and to create an adequate light footprint for your plants.
They also come with reflective material to produce additional light. Hoods boost the amount of light that’s sent to your canopy below through the use of reflective material, such as mylar, white coatings, and reflective aluminum.
Most hoods have a glass bottom and two vent holes. When paired with ducting and an inline fan, hoods efficiently trap the hot air produced from HPS bulbs. Once trapped, your inline fan and overall ventilation system will pull or push this heated air out of the grow space.
Unless you have a completely air-conditioned grow space, it’s uncommon to hang HPS bulbs without a hood.
When searching for the best HPS grow light, you’ll want to look within these categories. Let’s take a look at the various HPS bulbs that are available.
The 150w HPS grow light is the smallest of the bunch. This is an effective closet space HPS light, and you won’t feel the significant heat or the wallet-draining effects from this bulb.
This is for those who don’t wish to go the LED, T5, or CFL route. When you still want to give your plants the benefits of what an HPS light has to offer, then the 150w HPS grow light should be your first choice.
The 150w HPS grow light always comes in an all-in-one package. When paired with a small ballast, this system doesn’t weight as much as the next size up – the 400w HPS grow light.
For most small-scale cannabis growers, 400w HPS grow lights have proven to be the best time- and-time again. These effective lights come in both all-in-one systems as well as in stand-alone bulbs. What makes a 400w HPS bulb such an effective option?
The 400w HPS grow light offers high yields with reduced heat production and electricity costs. This alone has convinced a plethora of growers across the planet, but are you convinced? With adequate planning and forethought, a 400w HPS grow light system is the perfect introductory light in the world of cannabis production.
A 400-watt HPS grow light will cover a 3’x3’ if you grow your cannabis plants in a certain way. When using a 400w HPS grow light, you should always focus on the canopy, not the undergrowth. This is because the light penetration found of a 400w HPS grow light doesn’t compare to that of a 600w or 1,000w HPS bulb.
This means that your cannabis plants should be short and bushy. The methods that are ideal when growing with a 400w HPS grow light is the Sea of Green (SOG) method or the Screen of Green (SCROG) technique. Both of these styles focus on the canopy, which is where the largest buds will grow.
If you plan on growing larger plants, then you should switch to a higher wattage. 400w HPS grow lights are ideal when they are placed close to the canopy. As the light is placed closer to the plant canopy, the coverage is reduced. This is the main resistance with a 400w HPS light, in which the constant battle of coverage and efficiency is fought.
Although you may think that a 400-watt HPS grow light is perfect for a small space, you should understand that these bulbs emit a large amount of heat for their size. You may be surprised when you open your 2’x2’ tent to see your marijuana plants wilting under the intense beam of a 400w HPS light.
If you place an adequate ventilation system in conjunction with a 400w HPS grow light system, then you’ll likely have an enjoyable growing season.
600w HPS grow lights are the most versatile grow light in the cannabis industry. You would think the 1,000w HPS grow light would win this award, but gram for gram, the 600w HPS light is the preferred wattage of the bunch.
600w HPS lights are known for their excellent canopy penetration, which makes them suitable for growing dense bushes to tall cannabis trees. With an additional 200-watts compared to the 400w HPS grow light, the 600w HPS variety produces a noticeable boost in cannabis bud production.
The primary goal of cannabis cultivation is for an abundant harvest. 600w HPS grow lights are the primary candidate for saving money on your electricity bill and improving your gram per watt ratio.
Many ask “ is the additional 200-watts worth the extra electricity costs?” The answer depends on the space that you’re growing in. Many veteran growers recommend the smallest grow area as a 3’x3’, but a 4’x4’ is typically considered optimal. With a 4’x4’ space, you’ll have adequate space for large or small cannabis plants.
You can further increase the versatility of a 600w HPS by buying a digital ballast that offers dimming options. By doing so, you can “future-proof” your grow space if you plan on expanding in the future. Most growers hold onto their 600w HPS lights because these can always be used in a wide variety of situations.
When it comes to heat, be prepared for a substantial increase in your grow room’s overall temperature. Once you open your grow tent or grow room, you’ll feel as though you’re walking into a rocket launch as the light floods from the HPS bulb.
If you have your ventilation system locked down, then you’ll notice that your cannabis’ leaves are lifting their leaves toward the light. It’s without a doubt that cannabis responds well to the bright light from 600w and 1,000w HPS lights.
These are the biggest HPS grow lights in the garden. If you’re looking for full-blown plant coverage, then look no further than the 1,000w HPS grow light. These lamps are known to push out breathtaking light, especially if you’ve never seen it in person.
As you ignite your ballast, you’ll be shocked to see how outrageously bright a 1,000w HPS grow light is. Soon after you fire up the bulb, you’ll also understand why this bulb is only meant for serious growers who utilize top of the line cooling systems. If you don’t have a dedicated AC system, then there’s no reason to use a 1,000w HPS grow light.
If you do decide to go the 1,000w HPS grow light route, then prepare yourself financially and mentally. This light will take your breath away in two ways: first with the sheer intensity of its light, and the second with the corresponding electricity bill.
If you’re a small-scale cultivator, it’s usually recommended to stay with the 600w HPS grow light series. If you’re a full-scale commercial producer that’s set up with top-of-the-line AC and investor funds, then the electricity bill will be the least of your worries.
It’s imperative that you don’t try to force a 1,000w HPS grow light into a small grow space. Your plants will suffer immediately if you try this, and you’ll set your harvest time back significantly. If you plan on using a 1,000w HPS grow light, a 5’x5’ grow space is the minimum area that you should provide.
Light penetration isn’t a problem when it comes to this behemoth of light, so you can rest assured if you grow SOG, ScrOG, tall plants, or cannabis bushes. Any and every style of cannabis growing is possible when you’re equipped with a 1,000w HPS grow light.
As noted previously, the price that it costs to run a dedicated 1,000w HPS grow light is significant. This is why this review focuses primarily on 400w and 600w HPS lights. If you’re sure that you’re capable of running a 1,000w HPS grow light, then you’ll find yourself producing too much cannabis.
Before you take the plunge, take a look at these essential factors to look for while searching the many HPS grow light products that are currently available.
When deciding which HPS grow light to go with, it’s of utmost importance to decide on a wattage. 400w HPS grow lights are ideal for small-scale cultivators that don’t have a desire to bump up their production any time soon.
If you go the 600w HPS route, then you’ll likely want to upgrade your room size sooner rather than later. As you know, 600w HPS grow lights increase your grow room’s versatility, as long as your ventilation system can handle it.
If your grow room looks more like a grow closet, then it’s recommended that you use a 400w HPS grow light and below. This is because, at a certain point, a 400w HPS bulb will be over-kill if the room is too small. You want to find the right balance between adequate coverage and light intensity. If you fall out of range on either of these two factors, then your overall efficiency will decrease.
The largest space that a 400w HPS grow light should be used in is a 3’x3’ room. If you have a larger area, your yield may diminish as you try to spread your light over a larger canopy.
When using a 600w HPS grow light, you should focus on covering a 4’x4’ to 5’x5’ grow space. As your grow space increases, you can easily add additional 400w to 600w HPS lights to accommodate the added room.
As with anything when it comes to growing cannabis, a predetermined idea of space should be your priority before buying an HPS light. This is because your available space will determine the light required.
Similar in importance to the size of your grow room is the size and number of plants that you intend to grow. The larger the plants, the more likely you are to want to use a 600w HPS light. If you have limited space and intend on growing in the SOG style, then a 400w HPS grow light will be enough.
Another thing to consider before buying an HPS grow light system is the ballast type. If you purchase an all-in-one system, such as a 400w HPS light, then you’ll receive a magnetic ballast. If you buy a stand alone ballast, you’ll have a choice on digital or magnetic.
As stated before, buying a digital ballast will afford you greater flexibility in the grow room. Dimming options are game changers, and this option will prove itself to be invaluable once you use it.
Alternatively, if you’re on a budget, then a magnetic ballast might be the right option for you. As you consider financial concerns with functionality, you’ll likely lean towards that of the digital ballast.
Digital ballasts are efficient, offer more customizable options, and start-up much faster than magnetic ballasts.
Not all 400w-600w HPS bulbs are created equal. Manufacturers play a large role in the reliability of an HPS bulb. Whether you buy an HPS grow light package or a stand-alone bulb, you should always look at who produced it.
The major players in the horticultural lighting industry are GE, Phillips, EyeHortilux, and iPower. There are cheaper varieties available, but you want the very best that the lighting industry has to offer because these are the bulbs that will power your cannabis garden.
As the lighting industry grows in efficiency, researchers have found that PAR (Photosynthetically Active Radiation) plays a significant role in plant growth. When lights contain an optimal PAR rating (400-700nm), plants are prone to vigorous growth. This revelation has pushed manufacturers to optimize their grow lights to be within this PAR range.
With this knowledge, it’s essential that you seek an HPS bulb that is well within the optimal PAR spectrum.
Aside from PAR, you’ll want to make sure that your HPS bulbs are, in fact, within the right color spectrum. Your bulb should display its color in the 550-600nm range. You should steer clear of HPS lamps that don’t present a wavelength range or products that fall far from this rating.
The internet offers us incredible insight that wasn’t always possible. It’s given us the ability to read other user’s ratings quickly before making a purchase. This insight is incredibly beneficial, even after doing countless hours of research.
It’s vital that you read as many reviews as possible on a given HPS bulb. Even if the website of an HPS manufacturer looks stunning, it won’t matter if the bulb doesn’t work according to the advertisements.
Besides our review on the best 400w-600w HPS grow lights available, there are many avenues where you can view what growers around the world think about a certain product. You’ll be surprised as to what you can find out about various HPS grow lights once you dive into the many reviews available online.
After taking careful stock of the advantages and disadvantages of each HPS grow light system, we came to the conclusion that the IPOWER 600w HPS was the best grow light in show.
Each of the options that were presented held onto a specific niche, and the iPower 600w HPS grow light system was the most versatile of them all. Although it doesn’t have the sheer power of the SPL Horticulture 1,000w HPS light, it remains the most balanced.
The 150w and 400w HPS lights are adequate for smaller closet-space grows, but could not transition into a larger room if need be. For this reason, the iPower 600w HPS grow light system shined brightly amongst its competitors as a jack-of-all-trades.
There are countless 600w HPS grow light systems on the market, but the iPower is one of the most affordable devices with a brand name. Coming in at an affordable price, this is a hard deal to pass up when compared to competing brands.
IPower has become a driving force in the lighting industry, ranking as one of the top HPS bulb producers on the market. Additionally, this package also includes a 600w MH bulb for when you’re vegging your cannabis plants to their adequate size.
The only fault that can be said for the iPower 600w HPS grow light system is its wing. The wing doesn’t allow users to attach ducting to pull the warm air out of the room directly. This can be an issue for those who don’t use a dedicated AC unit, but then again, you should have an efficient ventilation system in place if using anything over 400-watts in the grow room.
The iPower 600-watt HPS bulb comes in the ideal range of 400-700nm, which makes it perfect for growing cannabis. The light penetrates through a dense canopy, making sure to coat the lower bud sites with bright light. To top it all off, the iPower 600w HPS grow light comes with a dimming option on the ballast.
As we mentioned previously, this ability is second to none. You can effectively dim your 600w bulb into the 300-450w range, which is perfect for young cannabis plants or if your room is too hot.
Now that you understand everything there is to know about HPS lighting, it’s time to make a decision. As long as you follow this guide, you’ll make a well-informed decision that will result in an efficient HPS bulb that produces an abundant harvest.
If you have any recommendations or comments, don’t hesitate to comment below. These guides are meant to encourage participation amongst the cannabis community, and your input is always appreciated. For further reading, join us at The Highest Crop for the most informative articles regarding everyone’s favorite plant – cannabis.