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When you’re looking to grow plants inside, you need optimal light to help them thrive. Natural light can be an option, but designated grow lights placed directly above your plants can help them grow strong.
Over the years, artificial lighting has advanced from incandescent to fluorescent lighting, and finally to LED lighting. LED stands for light-emitting diode, and these grow lights are generally considered the best available option because they mimic the sun’s natural light.
There are many options for indoor LED grow lights on the market, but not all of them are built the same. When selecting a fixture, you’ll want to consider quality, quantity, lifespan, heat, cost and energy efficiency.
If you grow plants at home and you’re looking for the best type of grow light for your indoor garden, this guide to LED grow lights can help you find the best option for your operation.
What Are LED Grow Lights?
LED grow lights are the most efficient type of lighting available. This incredible feat of technology is used in some of the most cutting-edge operations for commercial growing and for hobbyist gardens. Many advances in the technology of LED grow lights have occurred within the past few years, evening out the playing field between them and high-intensity discharge grow lights, also known as HID lights, that are commonly used across the country in indoor gardens.
LED lights are incredibly efficient, giving off a minimal amount of heat energy and using low amounts of electricity. LED grow lights combine advanced optics, thermal management engineering and precise spectral outputs to convert nearly all of the consumed power into light energy that is growth-targeted. This how an LED grow light can produce great yields and consume less energy than its HPS counterpart.
These lights emit light in a specific range, which means plants get only the light they need and no more. You won’t need to worry about wasting electricity with light that your plants won’t use. LED lights, also require very little maintenance — usually just occasional cleaning. From start to finish, growers typically use a single LED grow light system, as many LEDs are optimized for the entire growth cycle. Additionally, some LED grow lights are adjustable and can be used for different phases of a plant’s growth.
How Do LED Grow Lights Work?
A grow light is an artificial light source that mimics the natural light plants typically get from the sun. Grow lights allow plants to grow without complete reliance on the sun for natural light, allowing gardeners to grow plants both outdoors and indoors.
How Does Photosynthesis Work?
Usually, plants depend on sunlight for photosynthesis. During this metabolic process, plants create their own food by using the energy the sun provides. Plants convert light energy into carbohydrates, or chemical energy, which they then use to flower and grow. Photosynthesis takes place in a plant’s leaves inside the chloroplast. The following are the steps of the photosynthesis process:
- Pigments inside the plant’s chloroplasts absorb specific kinds of light energy.
- This captured light energy is used for making high-energy electrons.
- The high-energy electrons use energy to create an energy source that is more stable.
- This stable energy source is used to combine carbon dioxide into carbohydrates and then give off oxygen.
Manufacturers of grow lights have utilized this knowledge to develop different kinds of grow lights that can emit light on a chosen spectrum and give plants the highest quality, most intense light possible.
Either a grow light is designed to incorporate a spectrum that is the most beneficial for a certain type of plant species or it is designed to mimic sunlight. Since a plant species may need different amounts and types of light during the different growth periods, indoor gardeners may require various types of grow lights to give their plants the best possible light throughout every stage of growth.
How LED Grow Lights Work
After being plugged into an outlet, LED grow lights use light-emitting diodes to generate light. These are small electronic components, which are made from two different kinds of semiconductor material. One has a positive charge — known as holes — and the other has a negative charge — known as electrons. A semiconductor and electroluminescence are also utilized in LED lights to generate light. In sophisticated LEDs, tiny reflectors help amplify this light and better focus it.
When voltage is applied properly over an LED, the electric current begins flowing through it, making the holes and electrons collide. This collision releases energy through photons in a process known as recombination.
Modern LEDs are bright and may use ultraviolet, infrared and visible light. Certain types of light affect flower and root formation and influence plant growth. Most plant species complete their normal growth cycle when exposed to both red and blue grow lights, and adding other colors like green, deep blue and far-red helps in the process and can result in plants of higher quality. In some cases, however, certain light colors by themselves can produce plants that have undesirable growth characteristics.
Here’s a look at how different colors and types of light affect plant growth:
- Blue light: The use of blue light stimulates the opening of the stomata — tiny openings on the leaves that control the uptake of carbon dioxide and water loss. Blue light also promotes the growth of thicker leaves, but the plants aren’t as tall as they may be under different light colors.
- Red light: Red light can help to start the flowering process as well as keep it going for longer. Red light alone also tends to make plants grow tall, but they have a stretched, elongated appearance and smaller leaves — often considered undesirable growth characteristics by themselves.
- Far-red light: If there is too much far-red light by itself, a plant will think it’s in the shade. However, some far-red light can help in the flowering process.
- Green light: While green light tends to be the least efficient for photosynthesis, it is still useful for the process. Greenlight can penetrate deeper into the leaf, and it can get to the lower leaves of a plant better than other colors of light, helping the lower leaves to photosynthesize as well.
- Orange light: Orange light toward the red end of the color spectrum can help encourage plants to photosynthesize. A portion of chlorophyll B tends to favor this light color.
- Yellow light: Yellow light by itself is not an integral part of photosynthesis, but some plant pigments can absorb it, and it can help some plants to flower. However, yellow light tends to make a plant grow lanky with a big internode length — the space between the branches on the primary stem of a plant.
- Ultraviolet (UV) light: UV light can also aid in regulating plant growth. While plants develop smaller leaves and shorter stems with UV light alone, the light does produce thicker leaves and tends to enhance leaf coloration — especially plants that have purplish colored leaves. Too much UV light, though, can burn the leaves.
Plants may react differently to each light treatment depending on the species or variety. A plant may also require different lighting depending on the stage it’s in, such as whether it’s in the flowering stage or the vegetative stage.
What Are Full-Spectrum LED Grow Lights?
A spectrum in which all colors are included is known as a full spectrum. Full-spectrum LED grow lights mostly resemble the sunlight. If a light has high proportions of green, then it will appear white to your eyes. Though this isn’t a crucial factor in growing plants, it makes working with these lights easier and makes it possible to visually inspect your plants.
Many growers want to use various lights through each cycle to help their plants grow, from the vegetative stage to the flowering stage. Purchasing full-spectrum LED grow lights can spare you from needing to buy a lot of equipment or many different kinds of light. Besides blues and reds, plants need some infrared and ultraviolet lighting. With a specialized full-spectrum lighting system, you can give your plants all of the light wavelengths needed.
How Do I Know If My LED Grow Light Is Full Spectrum?
LED full-spectrum lights have a more natural light appearance to them. This is because these lights are adding specialized reds and blues, along with ultraviolet and infrared in many cases, to predominantly white diodes. When these are all combined, the light emits a sun-like glow with somewhat of a pinkish hue.
Features of full-spectrum LED lights include:
- Cooling system: Even though LEDs run cooler than other sources of light, they’ll still put off some heat. As such, most LED systems include cooling systems to improve operating efficiency.
- Warranty: You may also want to choose a full-spectrum light that offers a strong, lengthy warranty. This will give you some peace of mind when you make your purchase.
- Switches: Some full-spectrum LED systems have switches built in to give you control over the types of light being used. This allows you to turn one light on, another light off and pick the right light for each stage.
Are LED Lights Good for Growing?
LEDs were once used only for remote controls and to transmit infrared light, as this is what makes remote controls work. LEDs were nearly always red and were later used in digital clocks. With the improvement of technology, however, LEDs and their uses also progressed. Today, LEDs are used several different things, such as:
- Camera flashes
- Household lighting
- Indoor gardens
How do LED grow lights perform? Many growers have seen success from growing their plants with full-spectrum LED lights. Since you won’t need to swap out any lights and your costs for running the system are so low, you can enjoy increased yields and profits. Little maintenance is required, and all you’ll have to do is adjust how much time your plants are being exposed to light so it mimics the change of seasons.
We can also measure LED grow light performance by comparing these lights to other grow lights on the market.
LED Lights vs. HPS Lights
When compared to high-pressure sodium (HPS) lights, LEDs are a simple but powerful and energy-efficient option for grow lights. HPS lights are more and more being perceived as bulky and less robust, and they also require periodic bulb changes, making them more expensive over the long term.
While HPS lamps emit heat that can be effective in a greenhouse setting, this can cause challenges for smaller growth chambers or vertical farms. On the other hand, LEDs are more compact, faster switching and better for the environment.
An LED grow light releases less radiant heat, which positively impacts the nutrition and moisture requirements of plants. HPS lights emit heat directly on the plants, increasing the temperature of the leaf surface and potentially overheating the plant.
LED Lights vs. Incandescent Lights
Compared to LED lights, incandescents are not nearly as good for growing plants and should not be used as your plants’ only light source. Incandescent lights are inefficient and use a lot of energy, even though they don’t produce much light output. These lights also emit predominantly yellow and red light, which causes seedlings to become lanky, overstretch and fall over.
However, incandescent lights can be used as a supplement during the flowering period for increasing the amount of yellow light, as this can help induce plants to flower.
LED Lights vs. High-Intensity Discharge Lights
High-intensity discharge (HID) lights include high-pressure sodium (HPS) and metal halide (MH). Traditionally, these lights are used to light large areas like warehouses, parking lots and gyms. Today, specialized HID lights are used for growing plants indoors. Compared to incandescent lights, they are more efficient and produce a large amount of heat.
HID lights are good for promoting fruit development and flowering, as they emit more yellow and red light. However, these lights aren’t the best light source for seedlings.
LED Lights vs. Fluorescent Lights
Fluorescent lights are well-suited for growing plants indoors. While these lights are more efficient than incandescent lights, they have a low output of light, which means you’ll need to put your lights a few inches above your plants. As such, fluorescent lights aren’t typically a good source of light for large plants. You may be able to use fluorescents on big plants if you place the lights above and next to the plant rather than just directly over the top of it.
Pros and Cons of LED Grow Lights
LED technology was once believed to be cost-inefficient and impractical. However, today’s LED grows lights are some of the best that has ever been on the market and are considered incredibly cost-effective. Below are the pros and cons of LED grow lights to consider before making your purchase.
Advantages of LED Grow Lights
When you choose LED grow lights, you can enjoy the following benefits:
- Have no need for ballast: LED grow lights don’t require a ballast and can be directly plugged into regular wall outlets.
- Have a longer lifespan: Compared to other light options, LED grow lights have a longer lifespan.
- Run cooler: LED grows lights tend to run quite a bit cooler than other lights, which can be incredibly beneficial if you are an indoor grower.
- Can be dimmed: Though other lights use full light intensity, these lights can be dimmed with an app or remote control, meaning they provide greater control of output and consume less power.
- Use less wattage: LED grows lights rival HPS lights in terms of production. Comparable HPS lights use roughly twice the wattage as LED lights, so you can enjoy great savings on your power bill by using LEDs.
- Are usually all-in-one fixtures: LED grow lights are easier to use in tight spaces, as they usually come in the form of all-in-one fixtures. This means these lights can also be placed closer to your plants in a confined area with little threat of heat damage and can help conserve space.
- Additional safety: Because LED grow lights don’t become hot compared to other lights, they are safer to work around.
- Are better for the environment: LED grow lights don’t use lead, mercury, gas or filament. These lights also don’t have a fragile glass bulb and are more versatile, durable, longer-lasting and efficient than incandescent lights.
- Emit specific wavelengths of light: LED grow lights can be designed to emit specific wavelengths of light, which gives the grower more control and the ability to learn which configurations are most successful for their given species. Even at the phenotype level, this strategy can be effective if you are breeding plants and collecting enough data to make well-informed decisions.
Choose LED grow lights if you want your plants to thrive, to keep your electricity bill low and to select an option that is better for the environment.
Disadvantages of LED Grow Lights
When you choose LED grow lights, you may experience the following disadvantages:
- Higher upfront cost: LED grow lights tend to come with a higher upfront cost. However, they also save you money over the long term due to their lower cost of operation.
- Produce little heat: These lights usually produce little heat. While this is an advantage for many situations, if you are growing plants with LEDs in a colder indoor area, you may need to supplement with extra heat.
- Not as standardized: LED grow lights aren’t currently as standardized across manufacturers as other options. This can make it more difficult to comparison-shop. However, the LED grow light market has made a lot of progress, and the design practices are becoming increasingly consistent.
What Are the Best LED Grow Lights?
Plants require photosynthetically active radiation, also known as PAR, for photosynthesis. This means you need to select a light spectrum that is tailored to the growth phase of your plant and that will be useful in the environment where you’ll be growing, such as indoors or in a greenhouse.
The Best Full-Spectrum LED Grow Lights
Some of the best light options available are full-spectrum LED grow lights. The following are the key factors to consider when determining which full-spectrum LED grow lights to purchase:
- Size: While other types of grow lights are cumbersome and bulky, full-spectrum LED grow lights are better for smaller spaces. The fixtures are generally more compact and don’t require reflectors or ballasts, which frees up space in your grow room or tent.
- Cost: These lights tend to be more expensive initially, but you’ll save money in the long term due to the increased efficiency. The lifespan of LEDs is much longer than the average HPS bulb, for example, and you will see these cost savings over time. You can operate a full-spectrum LED grow light setup for many years before you’ll need to replace it.
- Heat: Your grow room’s temperature is a crucial variable, and grow lights can contribute to rising temperatures. This is why ventilation is so essential in a grow room. However, full-spectrum LED grow lights run cooler, which means this won’t be as much of an issue. This is especially advantageous if you’re growing plants in a warmer climate.
Find the Right LED Grow Lights You Need
Do you grow plants at home? If so, you need the best LED grow lights. At HTG Supply, we can help you find the right products that will allow you to get your home growing operation running. We are one of the fastest shippers in the industry, and our large selection of products is unmatched by competitors.
We are one of the fastest-growing suppliers for indoor gardening in the U.S., and we have locations in Pennsylvania, North Carolina, Florida, Maine, Massachusetts, Maryland, Connecticut, Oklahoma, Colorado and Michigan. You can count on us at HTG Supply for quality products and service. Browse our LED bulbs today to find the grow lights you need.