Grow Lights for Plants: Importance & How to Choose The Best One

Grow Lights for Plants – Choosing the Best One

Indoor gardening is different from traditional outdoor gardening in terms of its supplies and techniques. Your indoor plants will thrive if you provide plants with adequate amounts of light. You can recreate the water, light, and temperature of outdoor gardening to trick plants into growing indoors as they believe they are in a more natural environment. However, this can be a problem indoors without large windows, a sunroom, or copious skylights. Gardeners can overcome this challenge by using house plant Grow Lights that provide false sunlight for plants.

What Are Grow Lights?

Outdoor plants use sunlight to get their energy to grow through chlorophyll in their leaves. This process is termed photosynthesis. It helps plants use carbon dioxide and water to produce food called glucose or starch, which further helps to release oxygen. On the other hand, electric lights can act as grow lights that help indoor plants to grow. Grow lights either mimic the sun in providing a similar light spectrum or offer a particular light spectrum needed by a specific kind of plant that is being cultivated. In such a case, the intensity of the lamps is varied to replicate outdoor conditions. Whether the plants are full-grown or starter seedlings, their desired photoperiod, luminous efficacy, spectrum’s accurate range, color temperature, and time are determined. Andrei Famintsyn, a Russian botanist, was the first to use artificial light for growing plants after his research in 1868.

Factors to Consider Before Choosing Grow Lights for Your Plants

Seasonal changes or lack of windows can make it tricky to provide enough light to your houseplants or cultivate a wide variety of plants at any climate and during any time of the year. Grow lights are specially designed to substitute natural sunlight. They help to stimulate photosynthesis by providing the correct color spectrum needed for the plant to grow and flourish. The right light fixture or bulb enables you to savor delicious tomatoes in the dead of winter or enjoy the aesthetics of beautiful violets year-round. Different varieties of Grow lights have their strengths and characteristics. Here’s a list of factors to consider before choosing Grow Lights for your plants.

 1. Color (Light Photosynthetic Spectrum)

Light spectrum measured in nanometers is helpful to know the wavelength of lights. We use different nanometres ranges for different growth phases of plants. Certain types of bulbs filter out the rays in the spectrum needed by your plants. Indoor plants need a light spectrum, ranging between 400 – 700 nanometres, also known as Photosynthetically Active Radiation (PAR). This rating is mentioned on the packaging of the bulbs. A 2700K bulb will be a good starting point for flowers but is not high enough for growing vegetables, which requires a 6500K bulb and is a wide-spectrum option.

2. Intensity

Plants are exposed to a certain amount of light. It depends on the kind of light, the strength of the bulb, and the position of the lights.

3. Duration

Photoperiod means the duration of time in which a plant receives enough light; day length. It is the developmental responses of plants to the relative durations of light and dark periods. Plants need 16-18 hours of exposure to external light each day to grow. More exposure doesn’t necessarily improve plant growth at any rate. Plants that indicate photoperiodism that use day length to trigger blooming should be exposed to under 12-14 hours of light in the stage of flowering. The cycle of darkness that follows should, however, be uninterrupted to form fruit and flowers well. A timer should ideally be used to control the duration.

4. Plant Kind and Growth Phase

Various kinds of plants may require different light intensities. Forest plants typically don’t need the same amount of light as tropical plants originating from a hot sunny climate need. Additionally, the amount of lights plants need are not the same at different phases of their growth. Of course, a full-spectrum grow light can aid in all stages of plant growth.

5. Placements

Correct placement of light is very vital for your indoor plants to induce photosynthesis. It is also crucial to choose the appropriate light with the best intensity and a supplemental light source to extend daylight. Additionally, full-cycle lighting in a space without any natural light should also be considered before choosing Grow Lights. Hot bulbs can burn plants and ruin the crop. In essence, plants placed far away from light absorb little heat. Typically, each square foot of the growing area of indoor plants needs 30 – 50 watts.

6. Cost

Small bulbs can be obtained for cheap, while large operations to set up a light source for growing plants can cost thousands of dollars.

Importance of Grow Lights

It is always beneficial to grow an indoor garden to save your plants from being attacked by garden pests, and you can harvest them all year round by controlling the weather. Here are the four reasons why grow lights are an indispensable part of an indoor grow system:

1. Limited Light

Grow light provides the plants with artificial light for photosynthesis, especially in rooms with lesser or no sunlight, especially in chillier months. Grow lights help plants to grow in the perfect dark-light periods.

2. Heat

The heat produced from glow lights lets the plants stay warm naturally.

3. Growing Food

Grow lights are suitable for growing indoor herbs and greens for yielding a steady supply of home-grown food.

4. Propagation

Propagation of indoor plants from seedlings is possible with the help of grow lights as they provide the right amount of light and warmth needed for healthy growth.

Various Grow Lights for Indoor Plants

You can either install grow lights for your indoor seeds before transplanting mature plants outdoors or add them to enhance the beauty of your interiors. With a dramatic indoor herb garden with floating shelves for year-round use, this guide will help you explore and understand its benefits and downsides.

1. LED


Hobby growers and commercial greenhouse farms mainly use LED Grow Lights since they consume less electricity and thereby cost less. However, these lights do not produce too much heat, which can harm seedlings and indoor plants. An LED unit can be a bit costly, but it is energy-efficient and doesn’t require much maintenance due to its low energy usage. As they last longer than other grow lights, LEDs are most cost-effective in the long run. The intensity of LED Grow Bulbs are more than fluorescent bulb and have a full-spectrum form. They are preferable for a wider square foot area of indoor plants as you can get a higher light intensity.

2. Fluorescent


Fluorescent lighting is mainly preferred for plant parents for providing light during winter and encouraging plants to flower. Moreover, it’s cheaper than other types of grow lights. However, fluorescent lighting provides less heat, which can be harmful to indoor plants. T5 and T8 bulbs are some of the most popular small grow light varieties of fluorescent lighting. CFL is a good option for small spaces and can be easily screwed into an ordinary incandescent light fixture. T12 bulbs are a good choice as grow light for houseplants that are beginning to produce seeds, as it supplements the natural window light. However, they must be placed within a very short distance from the foliage to have a considerable effect.

3. HID


Metal Halide (MH) and High-Pressure Sodium (HPS) are two types of HID. Your HID light choice will depend on the type of indoor plant you have. It is generally recommended for diligent gardeners as a particular category of light fixtures is needed for them. Moreover, they emit a lot of heat and consume a lot of energy, resulting in higher electricity bills. Nevertheless, they are widely used because the light enters the plant foliage more than other light sources.

Which Plants Can Benefit From Grow Lights?

Most indoor plants can generally thrive in any light, but some indoor plants will grow happily and healthily under grow lights. Here are the varieties that benefit from grow lights:

1. Succulents

Succulents usually survive under bright direct or indirect sunlight. So they need enough light from grow lights during the winter season.

2. African Violets

The African Violet plant blooms best when placed under grow lights.

3. Orchids

Orchids need a minimum of 10 hours of light and correct temperature and humidity to grow well.

How To Install Grow Lights

One has to consider the area of your indoor garden plot, plant species, and the bulb type before installing grow lights. Here are a few basic instructions to get you started.

1. Area of the Indoor Garden

Whether it’s a single shelf, a basement area, or an entire room, pot plants and beddings should be set according to the space available for your indoor-grade plants. Group the pots or trays 4 to 8 inches apart to leave room for growth and easy access for pruning and care as per the type of plant.

2. Number of Bulbs

One or more bulbs or light sources may be needed to illuminate the entire growing area brightly. Primarily, edible plants require at least 30 watts per square foot, but fruiting species like tomatoes need 40 to 50 watts per square foot to produce abundant high-quality crops. Multiply the square footage of the growing area by the number of watts you plan to provide between 30 and 50. Next, divide by the number of watts supplied by the bulbs you use.

3. Light Rack

Support the bulbs over the plants at a proper height unless you’re growing plants that will remain stagnant at the same size throughout their lifespan. As the plants grow, the light rack needs to be raised. You can do this by using a pulley or hanging the light fixtures with metal chains to adjust the height by changing the links of the light fixture.

4. Add the Necessary Accoutrements

Plug your lights into a timer so that they receive enough amount of light and at the same time each day. If your lights produce temperatures above 80 degrees in your growing area, a ventilation system should be installed to prevent heat stress. Reflectors and all sorts of other grow light accessories can be used to achieve optimum results.

For How Many Hours Must a Grow Light Be Left On?

Indoor plants require more hours of light than those grown outdoors. Room set up, reflector, developing style, surrounding environment may also affect the lighting needed. Be sure to observe the growth of plants and adjust the light power accordingly. Most vegetables and flowering plants need 12 to 16 hours of light per day. Ensure that most plants receive at least 8 hours of darkness per day, which is crucial for the plant growth cycle. Check the seed packaging or plant tags, or ask at the nursery for specific suggestions. Grow lights should be turned off every once in a while as no one likes to work round the clock – not even plants!

Using the artificial light from grow lamps allows you to grow indoor crops year-round. The truth is that there is no one simple answer to the perfect grow light. Your budget and growing needs should be the determining factors for choosing a grow light for your situation.

Also Read:

Gardening Tips & Ideas
How to Save Your Dying Plants
How to Choose the Best Soil for Plants

Previous article «
Next article »