Of all the hardware used in an indoor garden or greenhouse few compare in importance to horticultural lighting. For indoor gardens, horticultural lighting is the sole energy source for the plants. In greenhouses, artificial lighting supplements the sunlight and gives the cannabis plants enough light energy to perform up to the grower’s standards. Whether a gardener is looking for a primary or supplementary lighting source, he or she should take the time to examine the lighting technologies available for horticulture. When making a choice, growers need to take into consideration the space they wish to illuminate and the cost of operation and maintenance. Currently there are four technologies used by horticulturists: high intensity discharge (HID), light emitting diodes (LEDs), fluorescents, and induction lighting.

High Intensity Discharge (HID)

High intensity discharge lighting includes both metal halide (MH) and high pressure sodium (HPS). HID lighting consists of three components: the ballast, the reflector or socket, and the bulb. Ballasts can be specific to the type of bulb (MH only or HPS only) or they can be switchable, or “smart” ballasts, which have the ability to operate either type of bulb. Most ballasts are specific to wattage; although some of the newer, digital ballasts can operate different wattage bulbs. The ballast connects to the power supply and acts as a power converter so the bulb receives the proper current. The reflector, or socket, is the component that connects the ballast to the bulb and the bulb itself is the component that actually emits the light. After receiving the proper current from the ballast, the bulb converts that energy into light. HID lighting is still the most popular choice for horticulturists for a few reasons. First, this technology has been around for a long time and is used in other industries. This means there are many manufacturers which helps lower the cost. Initial cost is not the only reason horticulturists continue to choose HID lighting. High wattage HID fixtures are very powerful and have the capability of penetrating a plant canopy along with covering a large area. For example, an indoor horticulturist who is using a 1000 watt HID light can adequately cover 25-50 square feet of garden space. Greenhouse growers looking for supplemental lighting can cover even more space with that same 1000 watt fixture. It is not uncommon for greenhouse growers to have a 1000 watt HID cover 100+ square feet for supplementary lighting purposes. Long story short, HID lighting has a low initial cost for a relatively large coverage area. This is the main reason HID lighting has remained so popular among horticulturists.

Light Emitting Diodes (LEDs)

Light emitting diodes, or LEDs, have been steadily gaining acceptance since their introduction within the horticultural community roughly ten years ago. Unlike other lighting technologies used in horticulture, LEDs are a solid state device which makes them extremely durable. LED fixtures usually consist of the panel of LEDs and a circuit board (generally housed within the lighting fixture). Many horticultural LEDs contain a heat sink and/or fan to help dissipate heat and increase the fixture’s life span. The biggest advantages of LED technology are longevity and the ability to customize the light spectrum. Plants have a heightened response to particular light wavelengths and LED technology has the ability to provide higher amounts of the particular wavelengths plants desire. LEDs are the only technology that has the potential to manipulate the ratio of these wavelengths into the perfect ratio for photosynthesis. The first few generations of horticultural LEDs were somewhat of a disappointment to the horticultural community because they lacked the intensity to compete with HID lighting fixtures. Many of the original LED fixtures contained only two wavelengths of light (red and blue) and utilized low wattage diodes. LEDs have made great strides since the first generation and today’s horticultural LEDs have the ability to compete with HID lighting in many ways. Many of the new LED fixtures contain more advanced wavelength ratios along with higher wattage diodes which allow for a greater penetration into the plant canopy. When comparing this technology to HID lighting, coverage is still somewhat of an issue. LED fixtures, unless they contain a special lens, are generally light-directional and the light will not spread out and cover a large area like a HID light. However, LEDs’ higher energy efficiency combined with a lower heat signature has many indoor horticulturists, at the very least, giving LEDs serious consideration. There are also many greenhouse gardeners who have had success using LEDs for supplemental lighting.

Fluorescents

Fluorescent lighting has been used in horticulture for many years. Thanks to some of the newer fluorescents that are much more efficient than the shop lights from your dad’s basement, fluorescents still have a solid place in horticulture. High efficiency fluorescents, like the T5 style, are still very popular among indoor horticulturists for vegetative lighting or for seedlings and clones. Fluorescent tubes, like the T5, automatically disperse light evenly throughout the entire length of the bulb. This is ideal for keeping young cannabis plants even in growth. Young plants grown under HID lighting (or any light source that is emitted from a single focal point) need to be continuously rotated to remain uniform. Unfortunately, as with the early generations of horticultural LEDs, fluorescents generally lack the punch needed to penetrate deep into a plant canopy for fruiting or flowering plants. Although some gardeners have had success fruiting under fluorescent lighting, HID lighting is a far more popular choice for fruiting plants. The light coverage of fluorescents is also limited to pretty much directly under the fixture which makes them less desirable for larger areas. Fluorescents can be a solid choice for supplementary lighting purposes in a greenhouse, especially when the grower is trying to limit heat in the greenhouse. When raised high enough above the plants, fluorescents can give adequate coverage in a greenhouse for supplementary purposes. However, if the garden requires more than four hours per day of supplementary lighting (like in a year round greenhouse) HID lighting may be a better fit.

Induction Lighting

Induction lighting is a technology that has recently been making headway in the indoor gardening industry. Induction lighting is unique in that it utilizes a sealed bulb design. This differs from HID and standard fluorescents because these technologies rely on electrodes which bring electricity into the bulb. Induction lighting utilizes microwave or radio frequencies to pass through the sealed bulb and excite the metals and gases sealed within. There are two types of induction lighting currently used in horticulture: induction fluorescents and sulfur plasma.

Induction Fluorescents

Induction fluorescents have all of the advantages of standard fluorescents but will not degrade as quickly. This allows them to retain a high CRI (color rendition index) and high amount of PAR (photosynthetically active radiation) for a long time. What this equates to is more uniform growth in the garden and much less maintenance. The initial cost of these fixtures is high but the gardener will not have to pay for bulb replacement throughout the entire life span of the fixture (usually 10-15 years). Like the T5 fluorescents, induction fluorescents are a great choice for vegetative growth or clones and seedlings. Induction fluorescents also have a coverage limited to almost directly under the light source. To combat this problem, some indoor horticulturists will place multiple fixtures close together to get adequate coverage.

Sulfur Plasma

Sulfur plasma is an induction technology that emits all its light from a small quartz sphere. The most promising thing about sulfur plasma is that it has the intensity of HID lighting with a more suitable light spectrum for plant growth. In fact, sulfur plasma lighting has the closest spectral light output to that of the sun than any other artificial light source. As with HID lighting, coverage and plant canopy penetration are not issues for sulfur plasma. Sulfur plasma is the newest lighting technology to be introduced to the horticultural industry and is currently very expensive. As more manufacturers produce sulfur plasma lighting, there will be a reduction in cost and, hopefully, a continued increase in efficiency. Sulfur plasma lighting could be the ideal lighting source for both indoor gardens and greenhouses in the future. Another advantage of sulfur plasma is longevity. As with induction fluorescents and LEDs, sulfur plasma lighting can last up to 10 years and will lose very little PAR and CRI over the course of the fixture’s life span.

When purchasing a horticultural lighting system and facing all the choices, gardeners have their work cut out for them. As the old saying goes “there is more than one way to skin a cat”. This could not be more true when it comes to horticultural lighting. All of the previously discussed technologies work well to grow plants. Some are more efficient with a higher initial cost while others are inexpensive and lose more energy to heat. Personal preference, an individual’s budget, and the specific use for the fixture are all things that a grower must weigh heavily before making his or her final decision about a lighting system. Some gardeners want to experiment with the latest and greatest in horticultural lighting technologies. Some gardeners want a reliable lighting system that will not break their budgets. In the end, it is ultimately up to the gardener which lighting fixture is the best fit for his or her garden.

Whether it’s to provide supplementary lighting or to extend the length of the photoperiod, some greenhouse growers are equipping their greenhouses with artificial light sources. Before purchasing a lighting system for a greenhouse, a grower should first determine which type of lighting system will best meet their needs.

T-12 Fluorescent

T-12 fluorescent lights are the standard four foot fluorescent lights commonly used in garages and shops. In fact, many people refer to T-12 fluorescents as “shop lights”. Although T-12 fluorescents are just fine for starting seeds indoors or illuminating indoor houseplants, they usually lack the intensity and efficiency to provide light to plants in a greenhouse.

T-5 Fluorescent

T-5 fluorescents are a more powerful and efficient version of fluorescent lighting. Still available in four foot lengths, the skinnier T-5 bulbs are 54 watts each. Specialty horticultural enhanced bulbs are available for T-5 fixtures in both the warm (red) and cool (blue) spectrums. The warm spectrum bulbs are rated around 3000 K and the cool spectrum bulbs are rated around 6400 K. During the fruiting or flowering stage of growth most plants require a higher percentage of red spectrum light. During the vegetative stage of growth plants require more blue spectrum light. Many T-5 fixtures hold multiple bulbs and allow “banks” of bulbs to be turned on or off. In other words, it is possible to set up a T-5 fixture to customize the light spectrum in your greenhouse. During the vegetative stage, the bank with the blue bulbs should be on. When the transition or flowering stage begins the banks with the red spectrum bulbs can be activated in order to give the plants the more appropriate spectrum for that stage of growth. Generally speaking, T-5 fluorescents are the most cost effective option for the hobby greenhouse grower.

Metal Halide

Metal halide is a type of high intensity discharge (HID) lighting that can be used in greenhouses. Metal halide lighting systems are more intense than fluorescent lighting fixtures and are a good choice when growing roses, tropical palm, or other plants that will require more intensity than fluorescents can provide. Metal halides generally produce a white or blue spectral output which makes them a good fit for vegetative growth. Metal halides are commercial quality fixtures that come in 400, 600, or 1,000 watts. Metal halide lighting systems require three components: the bulb, the ballast and the reflector or socket base. These lighting systems create a good amount of heat and can be quite expensive to operate. However, in some cases, metal halide is the only way to provide plants with the intense blue light spectrum they require for vegetative growth.

High Pressure Sodium

Like metal halide, high pressure sodium is a type of HID lighting. These lighting systems are also available in 400, 600, and 1000 watts. The biggest difference between high pressure sodium and metal halide is the spectral output. High pressure sodiums provide a good amount of red spectrum. This makes these lighting systems a great fit for fruiting or flowering plants. Since high pressure sodiums are also a type of HID lighting system, they will also require a ballast and reflector or socket.

If you have determined that your greenhouse will require a HID lighting system and you plan to provide artificial light during the plant’s vegetative and flowering stages, you should look into a convertible ballast. Convertible ballasts allow the grower to use both metal halide and high pressure sodium bulbs in the same fixture (but not simultaneously). A grower can use his or her metal halide bulb during the vegetative stage and then switch to a high pressure sodium bulb during the flowering stage.

LEDs

There is certainly an emerging opportunity for LED lighting systems to be incorporated into the greenhouse. Consumers should be aware that LEDs are very spectral specific and they need to make sure the LED light system they purchase provides the spectral output required by their plants. Unfortunately, there are a lot of variables to consider when comparing LED lighting fixtures. The light spectrum, actual wattage, and type of lens used are all things to consider when purchasing a LED system. There is also a wide variance in overall quality. Many of the cheap LED fixtures will not stand up to the conditions found within a greenhouse. There is no doubt that LED lighting systems will continue to shape the future of horticulture but it is important for consumers to closely examine what they are purchasing.

Background information was provided by ArcadiaGlasshouse.com.

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Revolutionizing the 1000w Fixture: The HSE NXT2

Although there is no shortage of new lighting technologies being introduced, high intensity discharge, or HID, lighting systems are still the staple for indoor horticulture. Most of the new lighting technologies are still unable to compete with the growth rates and yields produced by high pressure sodiums and metal halides. While many manufacturers are concentrating their efforts on reinventing the wheel, other companies are putting their efforts toward improving the efficiency of HID fixtures. This is exactly what P.L. Light Systems has done with their revolutionary HSE NXT2 1000w fixture. In fact, the HSE NXT2 could very well be the pinnacle of 1000w horticultural fixture designs.

The Design

When designing the HSE NXT2, P.L. Light Systems took everything they learned from developing past models and set out to develop the most technically advanced fixture available to the horticultural market. The HSE NXT2 has an electronic driver which allows for quiet and efficient operation. The HSE NXT2 also utilizes an all-new custom aluminum ballast compartment with built-in heat fins which reduce the electronic driver’s operating temperature by 6%. The reduction of operation temperature increases both the efficiency and longevity of the unit. Another change to the ballast itself is a hinged compartment which makes servicing super simple. P.L. Light Systems also incorporated a breathable membrane in the HSE NXT2 which keeps dust and dirt out but still allows for excellent ventilation. This ventilation around the ballast equates to even cooler operation and increased longevity. P.L. Light Systems redesigned the lamp holder assembly as well. The new single-part casting with lock sockets makes bulb changes much quicker and easier.

Double Ended Lamp

The HSE NXT2 utilizes a HPS 1000w double ended lamp which has increased light levels by up to 20%. Double ended bulb technology has actually been used in other sectors for years but only recently has been introduced to the horticultural industry. There are many benefits to double ended (DE) technology. The most significant benefit to horticulturists is extended lamp life. In fact, DE bulbs degrade about half as fast as standard mogul-based bulbs which means they can be used for horticultural purposes twice as long. The other huge advantage of DE bulbs is an increased light output level.

Reflector Options

To best meet the demanding needs of indoor horticulturists, the HSE NXT2 has two distinct reflector options: the Alpha or the Beta. The Alpha reflector is designed for uniformity and the most even dispersion of light levels possible. The Beta is designed to produce a more focused output for increased light levels.

There are many light technologies for horticulturists to choose from. High intensity discharge lamps, especially double ended bulb fixtures, are sure to remain the industry standard for some time. The HSE NXT2 may very well be the best lighting option currently available to horticulturists. If you are going to grow, you might as well grow with the best. Check out the HSE NXT2 today!

For more information about the HSE NXT2 and other P.L. Light Systems products, please visit: Urban-Gro.com.

High intensity discharge lighting includes both metal halide (MH) and high pressure sodium (HPS). HID lighting consists of three components: the ballast, the reflector or socket, and the bulb. Ballasts can be specific to the type of bulb (MH only or HPS only) or they can be switchable, or “smart” ballasts, which have the ability to operate either type of bulb. Most ballasts are specific to wattage; although some of the newer, digital ballasts can operate different wattage bulbs.

The ballast connects to the power supply and acts as a power converter so the bulb receives the proper current. The reflector, or socket, is the component that connects the ballast to the bulb and the bulb itself is the component that actually emits the light. After receiving the proper current from the ballast, the bulb converts that energy into light.

HID lighting is still the most popular choice for horticulturists for a few reasons. First, this technology has been around for a long time and is used in other industries. This means there are many manufacturers which helps lower the cost. Initial cost is not the only reason horticulturists continue to choose HID lighting. High wattage HID fixtures are very powerful and have the capability of penetrating a plant canopy along with covering a large area. For example, an indoor horticulturist who is using a 1000 watt HID light can adequately cover 25-50 square feet of garden space. Greenhouse growers looking for supplemental lighting can cover even more space with that same 1000 watt fixture. It is not uncommon for greenhouse gardeners to have a 1000 watt HID cover 100+ square feet for supplementary lighting purposes. Long story short, HID lighting has a low initial cost for a relatively large coverage area. This is the main reason HID lighting has remained so popular among horticulturists.

Of all the components that make up a successful indoor garden none are as important as the horticultural lighting. Although it is a combination of many variables that ultimately determines the success of a horticulturist, the single component responsible for providing the energy for growth comes from the horticultural lighting. One of the most important parts of a lighting system is the reflector. It was not long ago that indoor horticulturists hung bare bulbs in a large room and let things grow wild. As more advanced light reflection technologies were developed, indoor horticulturists started to pay closer attention to the light energy and how to maximize its use in the grow room. Although the first few generations of reflectors would be considered inefficient by today’s standards, they were a big step forward from hanging bare bulbs. Reflectors, like other hardware used by indoor horticulturists, have evolved rapidly, especially in the last 10 years or so. One company that stands out in terms of research and development is P.L. Light Systems.

P.L. Light Systems develops and manufactures innovative fixtures, lamps and reflectors designed to optimize light distribution. P.L. Light Systems realizes that different crops have different lighting needs and so they have developed multiple reflectors for varying crops and applications. All of P.L. Light System’s reflectors are high performance reflectors and are a product of extensive research and development. Each reflector has its own associated applications and specific properties. When examining a P.L. Light reflector it doesn’t take a light scientist to see that these reflectors would outperform the boxy reflectors commonly sold within the industry. Remember, a reflector with corners means a reflector with dead spots. This equates to less light reaching the plant canopy.

As our knowledge of plant physiology has increased, the way we measure and calculate light energy relative to plants has changed. Until fairly recently the indoor horticulture community viewed lumens per area or watts per square meter as a valid way to calculate light intensity. It has now become almost common knowledge that plants do not see light in the same way humans do. There are particular wavelengths of light that affect photosynthesis and those don’t necessarily correspond to the light that the human eye is sensitive to. In other words, we have learned that lumens are for humans and that photo synthetic active radiation (PAR) is what horticulturists should be concerned with. For indoor horticulturists, one of the most accurate representations of light energy is expressing the amount of micromoles (µmoles) per meter squared.

Unfortunately, providing cutting-edge light calculations is not common practice for most lighting manufacturers. Few companies understand the need for high quality equipment and comprehensive lighting advice. Many indoor horticulture companies sell products that are generic and not tailored to any specific purpose. Companies that sell the same outdated technologies make companies like urban-gro stand out even more. Not only is urban-gro a licensed distributor of P.L. Light Systems but they also provide custom light plans to help their customers achieve the optimal light levels for their indoor gardens. The detailed light plan can be developed for a specific crop and a given space  New indoor gardeners looking to set up their garden or experienced growers looking to retrofit their growing facility should visit Urban-gro.com to take a closer look at P.L. Light Systems. Urban-gro will provide a scientific light calculation which includes a light uniformity percentage and average micromoles at a given distance from the light source. In other words, a grower will know exactly how much usable light will be reaching the plant canopy.

The more information a grower can gather about a light fixture’s light energy output, the more efficiently the garden can be set up. Comprehensive light plans, like those offered by urban-gro, help growers maximize return and fully understand the variables that go into optimizing an indoor horticultural lighting system. After all, Isn’t it a functioning lighting system that drives the production of any indoor garden? Growers who set up their horticultural lighting in the most efficient way possible are sure to receive abundant yields and the highest return on their investments.

Do your homework. If you have questions feel free to contact urban-gro. Don’t your plants deserve the best?

Light emitting diodes, or LEDs, have been steadily gaining acceptance since their introduction within the horticultural community roughly ten years ago. Unlike other lighting technologies used in horticulture, LEDs are a solid state device which makes them extremely durable. LED fixtures usually consist of the panel of LEDs and a circuit board (generally housed within the lighting fixture). Many horticultural LEDs contain a heat sink and/or fan to help dissipate heat and increase the fixture’s life span.

The biggest advantages of LED technology are longevity and the ability to customize the light spectrum. Plants have a heightened response to particular light wavelengths and LED technology has the ability to provide higher amounts of the particular wavelengths plants desire. LEDs are the only technology that has the potential to manipulate the ratio of these wavelengths into the perfect ratio for photosynthesis.

The first few generations of horticultural LEDs were somewhat of a disappointment to the horticultural community because they lacked the intensity to compete with HID lighting fixtures. Many of the original LED fixtures contained only two wavelengths of light (red and blue) and utilized low wattage diodes.

LEDs have made great strides since the first generation and today’s horticultural LEDs have the ability to compete with HID lighting in many ways. Many of the new LED fixtures contain more advanced wavelength ratios along with higher wattage diodes which allow for a greater penetration into the plant canopy. When comparing this technology to HID lighting, coverage is still somewhat of an issue. LED fixtures, unless they contain a special lens, are generally light-directional and the light will not spread out and cover a large area like a HID light. However, LEDs’ higher energy efficiency combined with a lower heat signature has many indoor horticulturists, at the very least, giving LEDs serious consideration. There are also many greenhouse gardeners who have had success using LEDs for supplemental lighting.

High intensity discharge lighting includes both metal halide (MH) and high pressure sodium (HPS). HID lighting consists of three components: the ballast, the reflector or socket, and the bulb. Ballasts can be specific to the type of bulb (MH only or HPS only) or they can be switchable, or “smart” ballasts, which have the ability to operate either type of bulb. Most ballasts are specific to wattage; although some of the newer, digital ballasts can operate different wattage bulbs. The ballast connects to the power supply and acts as a power converter so the bulb receives the proper current.

The reflector, or socket, is the component that connects the ballast to the bulb and the bulb itself is the component that actually emits the light. After receiving the proper current from the ballast, the bulb converts that energy into light. HID lighting is still the most popular choice for horticulturists for a few reasons. First, this technology has been around for a long time and is used in other industries. This means there are many manufacturers which helps lower the cost. Initial cost is not the only reason horticulturists continue to choose HID lighting.

High wattage HID fixtures are very powerful and have the capability of penetrating a plant canopy along with covering a large area. For example, an indoor horticulturist who is using a 1000 watt HID light can adequately cover 25-50 square feet of garden space. Greenhouse growers looking for supplemental lighting can cover even more space with that same 1000 watt fixture. It is not uncommon for greenhouse gardeners to have a 1000 watt HID cover 100+ square feet for supplementary lighting purposes. Long story short, HID lighting has a low initial cost for a relatively large coverage area. This is the main reason HID lighting has remained so popular among horticulturists.

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