How to Choose the Right Indoor Gardening Light

Abstract: When it comes to indoor gardening, it is necessary to provide adequate lighting for your healthy plants. Since natural sunlight may not always be available or sufficient, using a grow light becomes essential for the healthy growth of indoor plants. So, let me share the secrets to successful plant growth and create a thriving oasis of greenery in your home or garden. Selecting the right grow light for indoor plants is the toughest task in providing your plants with the optimal light conditions they need to flourish.

Whether you’re just a beginner or an experienced plant lover, in this article, we will walk you through the essential steps of choosing the perfect grow light for your indoor plants. As a result, you become an expert plant parent and witness your plants growing in a way you’ve never experienced before.

What Type of Lighting Do Plants Need?

The first rule of indoor plant cultivation is that not all lighting is created equal. This means that, in the world of plants, they do prefer a specific range of light. This range is known as photosynthetic active radiation (PAR) and describes wavelengths of light between 400-700 nanometers. For humans, the majority of light looks the same; however, plants experience PAR lighting in a very different way.

When exposed to usable light, such as the light in between 400-700nm, plants undergo photosynthesis, phototropism, and photoperiodism. These three functions are the reason why plants can grow leaves, turn towards the light, and eventually flower.Therefore, when choosing the right grow light for your indoor grow – you’ll need to find a grow light with an optimized PAR range that caters to your plant’s needs. Let’s take a look at the two dominant colour spectrums of light that are commonly used for growing plants indoors.

The White and Blue Spectrum of Light : As the spring comes to a close and summer begins, the sun reaches its apex in the sky. Not only are summer days long, but the light produced by the sun is also incredibly bright. When measured, this light falls under the white and blue spectrum of the PAR range. Research shows that the bright light associated with the 400-470nm range (bluish-white) promotes strong vegetative growth and increased rooting. It’s for this reason that many indoor cultivators choose to use grow lights that produce light within the 400-470nm range while vegetating their indoor crop.

The Red and Orange Spectrum of Light: As the summer months wane and autumn sets in, the sun no longer reaches its apex in the sky. Instead, the sun begins to skirt across the horizon as the days become shorter – and colder. The light that’s associated with the angle of the sun during this transition to shorter days is 620-700nm (orange-red). Research indicates that the red-orange colour spectrum is a prime influencer for plants to begin the flowering process.

In regards to indoor plants, cultivators use this natural mechanism to their advantage. By harnessing photoperiodism, indoor growers use grow lights that produce light in the 620-700nm range to promote robust flowering.

An Introduction to Common Indoor Grow Lights : When it comes to indoor grow lights – there are four types that are commonly used: high-intensity discharge lamps, plasma lamps, LED, and CFL. Let’s take a look at each and their associated technologies.

HID Lamps : High-intensity discharge lamps are the most popular lighting appliances for indoor cultivators. The primary reason behind the popularity of HID lamps is due to their sheer output of light.
A 400W high-pressure sodium (HPS) lamp : HID lamps typically come in various wattage formats, such as 150 watt, 400 watt, 600 watt, and 1,000 watt. The higher the wattage – the stronger and more intense the light. Furthermore, HID lamps are available in the blue-white range (metal halide) and the red-orange range (high-pressure sodium). This means that indoor growers can fine-tune their indoor garden according to the plant’s stage of growth. HID lamps require a heavy ballast, which is the source of the power that’s sent to the bulb. As the power reaches the bulb, the arc tube and electrodes produce a sustained current of electricity. However, HID lamps are power-intensive, which means they consume a large quantity of electricity and produce an abundance of heat. Although HID grow light systems are affordable – they are by far the most expensive because they require a significant amount of electricity to power them and to cool down.
LED Lighting : LED lighting is another popular product to use for indoor plant cultivation. LED grow light systems are composed of a multitude of diodes, which are powered by an internal ballast. A typical high-end LED grow light that is primarily equipped with white (full-spectrum) LEDs and supplemented with 660nm pure red LED chips. Not only are LEDs capable of emitting an abundance of light – they are typically composed of diodes that emit a specific colour range. It’s because of this that many LED lights are considered full–spectrum. This means that a single LED light can emit red, blue, white, and orange light that’s optimized for plant growth. LEDs are touted for their decreased heat output, reduced electricity consumption, and overall increased efficiency. Although LEDs are one of the most expensive grow lights around – they generally pay for themselves within a single year of use when you factor in the energy savings.

How To Choose One Light Over the Rest : When it’s time to make a decision on which indoor grow light is best for you – it’s time to look at various factors that are specific to your indoor grow setup. The first aspect to consider is the space of your grow room and the number of plants that it will contain. If you have a large number of plants and an abundance of space, then multiple LEDs or HID bulbs will suffice.

Large and spacious grow rooms often use either high-power HID lights or bar-style LED lights : If you have a small area, then a single LED or HID bulb will be adequate. The overall objective with indoor growing is coverage, which means that it’s essential that the indoor grow light that you choose covers the plant canopy entirely. The second aspect to consider is heat emission. LED grow light systems are by far the most efficient grow light systems because they do not emit an abundance of heat. Alternatively, HID bulbs produce a significant amount of heat, which will force you to use more electricity from an AC unit to cool the room down.

Which is Right for You?

When it comes down to choosing the best indoor grow light – it all depends on you. By considering the space of your grow room, the number of plants, your local environmental factors, and your available budget – one of these indoor grow lights will be right for your indoor plants.

Key Factors to Consider:

Light Spectrum:
Plants use light for photosynthesis, and different wavelengths of light (colours) are crucial for different growth stages.
1. Blue Light (400-500 nm): Promotes vegetative growth and helps with the development of strong roots and stems.
2. Red Light (600-700 nm): Encourages flowering and fruiting.
3. Full Spectrum Light: Mimics natural sunlight and is effective for all stages of plant growth. It combines blue, red, and other light wavelengths.
Light Intensity:
Plants have varying light intensity requirements based on species.
1. Low light: Plants like ferns or snake plants.
2. Medium light: Herbs like basil and parsley.
3. High light: Vegetables and flowering plants (e.g., tomatoes or peppers).
The intensity should be sufficient to avoid etiolation (stretching of plants) or leaf scorch.
Light Duration (Photoperiod):
The length of time a plant is exposed to light affects its growth cycle.
1. Short Day Plants: Need long periods of darkness (e.g., chrysanthemums).
2. Long Day Plants: Require longer periods of light to flower (e.g., spinach, lettuce).
3. Day-Neutral Plants: Flower regardless of light duration (e.g., strawberries).

Plants may need anywhere from 12 to 16 hours of light per day, depending on their species.

Type of Light Source:

Incandescent: Warm light but inefficient and not suitable for plant growth.
Fluorescent: Energy-efficient and commonly used for seedlings and herbs. Best for low to medium light needs.
LED (Light Emitting Diode): Highly energy-efficient and customizable in terms of spectrum. Can be tailored to the needs of specific plants. Full-spectrum LEDs are ideal for all stages of growth.
HPS (High-Pressure Sodium): Excellent for flowering and fruiting stages but less efficient for vegetative growth.
MH (Metal Halide): Great for vegetative growth but less efficient than LEDs.

Distance from Plants: The intensity of light diminishes as the distance between the plant and the light increases. Research often discusses optimal distances for different types of lights, for instance, LEDs should typically be placed closer to plants than fluorescent lights.

Environmental Factors: Temperature and humidity levels in your indoor garden can affect how light is absorbed by plants. Some studies recommend adjusting light intensity or duration based on your local conditions.

Conclusion: In conclusion, choosing the right indoor lighting is essential for creating a functional, aesthetically pleasing, and energy-efficient environment. The key factors to consider include the type of lighting—ambient, task, and accent—and the proper selection of light sources, such as LED, fluorescent, or incandescent bulbs, based on their energy efficiency, color temperature, and lifespan. Understanding the specific needs of each room and activity, whether it’s for reading, cooking, or relaxation, plays a critical role in determining the appropriate lighting. Additionally, considerations such as dimming capabilities, smart lighting options, and the integration of natural light can enhance the overall indoor atmosphere. By carefully balancing these elements, individuals can create well-lit spaces that support productivity, comfort, and well-being, while also reducing energy consumption and maintenance costs. Ultimately, the right lighting choice is an investment in both the functionality and aesthetics of any indoor space.

Reference:

LED lighting in Indian homes: A case study on adoption and benefits. SEF India. Retrieved from https://sustainableenergyfoundation.org
Choosing the right lighting for your home. National Lighting Bureau. Retrieved from https://www.nlb.org
Lighting design for the modern home: Enhancing functionality and aesthetics. Lighting Research & Technology
Guidelines for indoor lighting in residential and commercial spaces in India. NILD. Retrieved from https://www.nildindia.org