Does Hydroponics Need Sunlight to Work?

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Hydroponics has completely changed the way I grow plants at home, allowing me to grow year-round and use my resources more efficiently. I started growing indoors with artificial light. And, as spring rolled around, I started to wonder if my plants needed natural sunlight, or if I could rely solely on artificial light.

I did some research and here’s what I found.

Hydroponics systems do not need sunlight to work effectively, but they do require a suitable light source, whether it’s natural or artificial. While sunlight can provide the necessary light for plant growth, the advantages of artificial lights make it a more popular choice for hydroponics growers.

In this article, we’ll explore the importance of light in hydroponic growth, discuss the benefits of using artificial light over natural sunlight, and provide tips on how to optimize your hydroponic system’s lighting for the best results.

The importance of light in hydroponic growth

Before we explore whether hydroponics systems work better with sunlight vs. artificial light, let’s first explore why light is important for plant growth.

Photosynthesis and plant growth

Light plays a critical role in plant growth through the process of photosynthesis. In this process, plants convert light energy into chemical energy, which is stored in the form of glucose.

Diagram of how photosynthesis works
A diagram explaining the process of photosynthesis

This energy is then used to fuel various plant functions, including growth, reproduction, and defense against diseases.

Light spectrum and intensity requirements

Different plants have different light spectrums and intensity requirements for optimal growth. Generally, plants need light in the blue and red parts of the spectrum, with blue light promoting vegetative growth and red light encouraging flowering and fruiting. The intensity of light required varies based on the type of plant and its stage of growth.

Benefits of sunlight in hydroponics vs. artificial light

1. The sun has a larger spectrum of light

Natural light is full spectrum, which means it contains all light wavelengths. If you have ever held a prism in the sunlight you’ll have noticed all the beautiful colors of the rainbow shooting out one end. These colors represent different light wavelengths, the most important of which are blue and red. Not all artificial lights can replicate the breadth of wavelengths that sunlight has.

Comparision of natura light spectrums vs. arteficial light sources (source: European Lighting School)

2. Natural light is free

One of the key advantages of using natural light over artificial light is that it’s completely free to use. Hydroponics systems can use quite a lot of energy to function and artificial lights can add quite a lot of cost to your monthly electricity bill.

For example, I recently worked out that I am spending around $18.56 a month on electricity to run the lights on my two hydroponic towers. That may not seem like a lot, but natural light would cost me $0.

If you want to work out your hydroponics systems’ electricity use I wrote a whole article on it, check it out here: How much electricity does a hydroponics system use?

Benefits of using artificial light in hydroponics vs. sunlight

1. Greater control over the lighting environment

One of the main benefits of using artificial light in hydroponic systems is the level of control it provides. If you buy the right lights, you can tailor the light spectrum, intensity, and duration to meet the specific needs of your plants. This control allows me to get stronger growth, and improved yields.

2. Extended growing seasons

By using artificial light, I can extend the growing season or even grow plants at home year-round. I can even grow plants at night. This is particularly beneficial if you live in an area where the growing season is short or where there is a harsh, unpredictable climate.

A white hydroponic tower garden outside in the
Setting up my new aeroponic tower garden in less than favourable conditions…

When I use arteficial lights vs. natural light I can guarnettee the conditons and environmental factors experienced by my plants. Conversely, growing hydroponics outdoors can be unpredictable, causing environmental fluctoations in humididty, temperature and light that can affect plant growth.

3. Optimizing space for indoor gardens

Artificial light sources can be placed closer to plants, allowing for more efficient use of space in indoor gardens (where most hydroponics systems reside). This makes hydroponic systems ideal for urban environments or locations with limited space.

Common artificial light sources for hydroponic systems

Fluorescent lights

T5 Fluorescent lights are a popular choice for hydroponic systems because they are energy-efficient and produce less heat than other light sources. They are low profile, and available in different light spectrums, making them suitable for various stages of plant growth from seedlings to maturity.

Fluorescent grow lights for hydroponics (image source: Hydrobuilder)

Some of the most popular on Amazon are the DuroLux T5 Fluorescent Grow Light System.

Light-emitting diodes (LEDs)

LEDs are another popular light soruce for hydroponics systems. They are very energy-efficient, long-lasting, and can be customized to provide specific light spectrums. They also produce less heat than other light sources, reducing the risk of overheating plants and the need for any additional cooling systems.

An LED lighting array (image source: The Spruce)

I personally use LEDs over Flourescent lights. Some of the best LED light arrays for hydroponics are those made by Spider Farmer.

Sunlight vs. artificial light: The verdict

So, do hydroponics systems need sunlight to work effectively? The answer is no, but they do require a suitable light source, natural or otherwise. Without the rigt spectrum and intensity of light your plants simply won’t grow. While sunlight can provide the full light spectrum and intensity for plant growth, artificial lighting offers several advantages, including control over the light environment, extended growing seasons, and space optimization.

Both sources of light have their advantages. Persoanlly, I use both natural light and artefical light in my hydroponics systems. In summer, I take my aerponic towers outdoors to use the free sunlight provided during the long days. In fall, and winter, I move my towers indoors and rig them up to high-quality arteficial lights. This works well and helps to keep costs down too in the summer months.

Final thoughts

Hydroponic systems don’t need sunlight, but they do require an appropriate light source to support plant growth. By understanding the role of light in plant growth, choosing the right artificial light source, and optimizing your system’s lighting, you can successfully grow a thriving indoor garden without relying on sunlight.

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William, an experienced consultant and passionate advocate for technology and sustainability, is the founder of Smarter Home Gardens. William's journey into gardening began with the purchase of his first home, which came with a small backyard garden. Despite initial challenges brought about by limited space, soil, and sunlight, William's determination to create a vibrant garden led him to research and experiment with innovative gardening technologies and sustainable practices. Driven by his lifelong enthusiasm for technology and sustainability, William explored various gardening methods, including vertical gardening, hydroponics, companion gardening, and composting. Through these efforts, he realized that it was possible to combine his passions with his newfound love for gardening. Smarter Home Gardens was born out of William's desire to share his research and experiences with others, helping them create smarter gardens that leverage cutting-edge technology and contribute to a more nature-positive world. The blog offers in-depth articles on innovative gardening technologies and methods, helpful 'how-to' guides, reviews of the latest gardening technology, and research on cost-effective garden maintenance solutions. William's commitment to sustainable and technologically-driven gardening has made him a trusted voice in the field. His enthusiasm for creating gardens that work with the planet, rather than against it, is evident in every post he shares on Smarter Home Gardens. Through the blog, William hopes to engage with a wider audience, encouraging others to join him on this exciting journey towards smarter, more sustainable gardens.

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