Infrared Grow Lights for Hydroponics That Work

Infrared grow lights bring a whole new dimension to hydroponic gardens. These special lights (operating at wavelengths between 700-1000nm) work like invisible helpers, warming up the plants just right. Plants really soak up this heat energy – it helps them grow bigger leaves and stronger stems, plus they tend to produce more fruit or veggies.

Most growers mix these with regular LED lights for the best results. Think of it like giving plants their own personal sunbath. The trick is hanging them about 24-30 inches above your plants, running them for 12-16 hours daily.

Want better yields from your hydroponic setup? Keep reading to find out exactly how to set up these lights for maximum growth.

Key Takeaway

1. Infrared grow lights help plants flower and grow taller.
2. They work best when combined with other light colors, like red and blue.
3. Using these lights can save energy and improve plant health.

What are Infrared Grow Lights?

Infrared grow lights are special lights that shine in the infrared spectrum, which is a kind of Infrared light, which is invisible to the human eye, holds significant importance for plant life. This light spectrum begins just past the visible red light, starting from approximately 700 nanometers (nm). While plants primarily require red and blue light for the crucial process of photosynthesis (food production), infrared light offers complementary benefits.

Functioning much like a hidden facilitator, infrared light aids plants in optimizing growth, particularly during flowering phases or when stem elongation is needed. Its role in plant development is intricate, notably through interaction with the plant’s phytochrome system. This invisible light contributes to various essential processes, such as enhancing flowering responses and assisting plants in managing their temperature.

Infrared light operates subtly, influencing plant behavior as they grow. It plays a crucial part in hormonal balance within the plant, helping to produce hormones that can trigger flowering or encourage vertical growth. This characteristic is especially advantageous in controlled environments like hydroponic systems, where plants are often grown in close proximity and vertical space management is key.

Consequently, the use of infrared grow lights presents a potentially valuable strategy for dedicated hydroponic cultivators. When combined with essential red and blue light sources, infrared light might help plants achieve their maximum potential, effectively providing them with a more comprehensive set of tools for beautiful and healthy development.

How Infrared Lights Fit Into Hydroponic Systems

Sometimes, you can almost feel the plants reaching—like they’re stretching up, not just for any light, but something deeper, warmer. That’s where infrared comes in. In hydroponic setups, where there’s no soil and usually no sun, infrared light gives plants a bit of what they’re missing. Especially in closed systems.

Plants grow in water rich with nutrients, but without sunlight, they rely on artificial lights. Full-spectrum LEDs usually cover it all—visible light, UV, and yes, infrared. That last part (infrared, usually in the 700–850nm range) plays a subtle but big role.

• Infrared light promotes flowering—tomatoes, peppers, and strawberries respond fast, blooming earlier and more consistently.
• It encourages stem elongation—which sounds technical, but really just means taller plants.
• Helps with dry matter accumulation—more biomass, more growth, more yield.

Studies show that using LED lights with infrared in hydroponic systems can nearly double plant height (from 10cm to 20cm in two weeks), increase leaf count by 40%, and boost dry mass by 30% over plants grown under traditional lighting. That’s not a fluke. It’s measurable.(1)

What infrared really does is mimic the heat signature of the sun. It signals to the plant that it’s in a warm environment—even when the air’s cool. So the plant responds by growing faster, trying to reproduce.

Anyone setting up a hydroponic system should probably choose LEDs with a built-in infrared range. Not just for the science—but because the plants seem to like it. You can almost see them lean into it.

Benefits of Infrared Grow Lights

Credits : Farmer Tyler

There’s a kind of quiet strength in infrared light. You don’t see it, but plants do—or at least, they feel it. In hydroponic gardens, that invisible push helps keep everything moving upward. Literally.

Infrared grow lights offer a few key benefits that go beyond just “extra light.” They actually shape how the plant grows and responds to its space.

• Boosts flowering and fruiting (especially in fruit-bearing crops like cucumbers, peppers, and tomatoes)
• Improves heat stress tolerance (plants under IR show lower signs of wilting or leaf curl)
• Reduces energy use (modern infrared LEDs can run for 50,000 hours with minimal power draw)

When plants absorb infrared radiation, their internal temps rise slightly—even if the room feels cool. That gentle warmth helps trigger flowering pathways, especially under 735–750nm light. Some researchers say this boosts phytochrome activity (the pigments that help track light cycles), so plants think it’s time to bloom.

And there’s a practical side, too. Older grow light systems (like HPS) burn hot and suck power. But high-efficiency LED panels with infrared diodes (often less than 100W per square meter) cut down on electricity use, reduce heat damage, and last for years. That’s not just good for the planet—it’s good for your wallet.

If you’re managing a hydroponic setup, add infrared to your light mix. Red and blue still do most of the heavy lifting—but IR brings everything together. A silent partner, working in the background.

Best Practices for Using Infrared Grow Lights

Infrared grow lights change the way indoor plants grow. But too much of a good thing? That’s where things get tricky.

Plants use red and infrared wavelengths (specifically 700–760 nm) to support stem elongation, leaf expansion, and flowering. Still, when infrared exposure gets too intense, it can cause stretching—tall, leggy growth that makes plants weak. That’s why most growers keep infrared under 10% of total light output. It’s not about blasting plants with heat; it’s about balance.

Some LED grow lights let users fine-tune spectrum settings. Full-spectrum setups often include red (660 nm), far-red (730 nm), and infrared. This is helpful during flowering, when plants respond to longer wavelengths. A typical hydroponic schedule? Around 16 hours of light per day during vegetative growth, cut to 12 for flowering. More light doesn’t always mean better growth—timing and intensity matter just as much.(2)

Tools help. A PAR meter (Photosynthetically Active Radiation) checks how much usable light actually reaches the canopy. Spectrometers, though more expensive, offer precise breakdowns. Watching leaf shape, color, and internodal spacing also tells a story.

Here’s a rule of thumb:

• Start with low IR settings (5–10%)
• Observe plant responses weekly
• Adjust based on strain-specific needs

For leafy greens, low IR works. For fruiting crops—like peppers or tomatoes—slightly more might help speed up flowering. Growers should also measure leaf temperature. If it’s more than 2°F higher than ambient, IR might be too strong.

A plant doesn’t need perfect conditions, but it does need consistency. Infrared grow lights support growth, but only when they’re part of a complete, thoughtful setup.

Practical Applications in Hydroponics

Hydroponic growers use infrared grow lights in a few clever ways. Most aren’t flashy—but they work.

One of the best applications? Fodder crops. Wheatgrass, barley, and rye grow fast with far-red and infrared supplementation. The boost in stem elongation helps with dense mat formation, and since these crops are harvested young, faster cycles mean more yield.

Stacked systems benefit too. Infrared lights (placed on lower or side tiers) help reach leaves that would otherwise sit in shadow. That’s common in NFT and vertical rack setups. Light penetration is limited when only top lights are used, especially in tight grow tents. Spacing matters—keeping lights around 12–18 inches away from foliage reduces the risk of burning while still improving lower canopy response.

Customising spectrum by plant type is also common. Basil prefers more blue and red. Tomatoes want more red and IR during flowering. Infrared helps activate the Emerson Effect—where red and far-red work together to increase photosynthetic rate. This matters more in fruiting stages than in vegetative ones.

According to 2023 market data, the global LED grow light industry (which includes infrared options) hit $3.2 billion. It’s expected to grow over 15% per year through 2030. That kind of market growth tells a story: indoor growers are finding new ways to boost yields without extra square footage.

Practical tips:

• Use IR panels for lower canopy in vertical farms
• Pair IR with red during flowering for fruit-heavy crops
• Monitor temps often (infrared = heat)

Hydroponics thrives on control. Infrared lights just give growers one more dial to turn.

FAQ

What are infrared grow lights and how do they help plants grow in water?

Infrared grow lights give off a special kind of light called infrared. This light helps plants in hydroponic systems grow better. Since hydroponics means growing plants in water instead of dirt, these lights work with regular ones to make stems stronger and flowers bloom more. The infrared spectrum helps plants grow faster and produce more food. Think of it like a super helper for your water garden.

How is infrared light different from other light colors for water-growing plants?

Infrared light has a longer wavelength than light we can see. Plants use it in a different way than red or blue light. While red and blue help plants make food, infrared light helps them grow better stems and flowers. Near-infrared light hydroponics gives plants an extra boost. It’s like a secret code that tells plants to grow in special ways.

Can infrared lights help plants flower better in water gardens?

Yes! IR LED grow lights help plants make flowers faster and more evenly in hydroponics. The infrared spectrum affects plant hormones that control flowering. It tells the plant to stop growing leaves and start making flowers. IR light and flowering acceleration go hand-in-hand, helping fruiting plants bloom sooner and grow better in water gardens.

How does infrared light help plants grow faster in water systems?

Infrared light helps plants grow faster by speeding up how their cells work. In hydroponic plant growth lighting setups, IR light boosts photosynthesis enhancement, helping plants turn light into energy faster. It also helps them take in nutrients quicker from hydroponic nutrient solutions. That’s how infrared and plant metabolism work together for fast, strong growth.

How does infrared light help plants make their own food in water gardens?

Photosynthesis is how plants make food using light. IR light doesn’t do this by itself, but it helps. Infrared wavelengths help plants open tiny holes in their leaves (called stomata), so they take in more air. This makes photosynthesis work better. IR light and photosynthesis enhancement work as a team in hydroponic indoor farming lighting systems.

How do plant hormones change when exposed to infrared light in water gardens?

IR light changes plant hormones like auxin, gibberellin, and cytokinin. These control how tall plants get, when they grow new leaves, and how seeds sprout. Infrared light and plant hormone modulation help plants grow stronger stems, more side branches, and better shapes in hydroponic gardens. IR light gives plants a healthy boost from the inside.

Why are infrared LED lights better than old lights for water gardens?

IR LED grow lights are cooler, use less power, and last longer than old infrared lights. New hydroponic LED grow light setups let you control the exact IR wavelengths your plants need. You can use IR LED grow light applications to match different growth stages. These lights also save energy, so your power bill stays low.

How does infrared light affect plants at different growing stages in water gardens?

Infrared light helps plants at every stage. During sprouting, it helps seeds wake up. During growing, it makes leaves thicker and stronger. During flowering, it speeds up blooming. For hydroponic lettuce grow lights, IR can slow down bolting and make leaves taste better. Matching IR light to plant growth stages helps them grow the best they can.

What should I know about how much infrared light to use in water gardens?

Using the right amount of IR light is important. Too little does nothing, but too much can hurt plants. Hydroponic LED light intensity control helps you manage it. Usually, IR light should be 10–20% of your total grow light power. IR light and plant stress response depend on the plant type, so start low and watch your plants.

How does infrared light change how plants and leaves grow in water gardens?

Infrared light affects how plants shape themselves. It helps with leaf thickness, leaf expansion, and better plant structure. In hydroponic vertical farming lighting, IR light helps prevent stretching and builds stronger branches. That means plants can hold more fruit and resist problems better.

How does the warmth from infrared light affect water-garden plants?

Infrared light thermal effect is gentle but helpful. IR LED grow lights warm leaves a little, helping plants control water and open stomata. In hydroponic deep water culture lighting, it helps balance leaf temperature while roots stay cool. The warmth improves nutrient flow and helps sensitive plants grow better without heat stress.

How can infrared light help plants take up nutrients better in water gardens?

IR light helps roots work harder. It warms the root area slightly, making them absorb nutrients better. Infrared spectrum light activates helpers inside plants that move minerals from root to leaf. In hydroponic smart farming lighting, this boosts calcium uptake and prevents problems like blossom end rot. Plants grow faster and use nutrients more wisely.

How does infrared light affect day and night sensing in water garden plants?

Plants sense day and night with a system called photoperiodism. IR light and plant photoperiodism work together. Growers use IR light to trick plants into thinking days are longer or shorter. This helps control when plants flower in hydroponic gardens. You can speed up or delay blooms using the LED grow light photoperiod strategy.

How long should I use infrared LED lights on my water garden plants?

Most hydroponic plants need 14–18 hours of light each day. IR light works best at sunset or early night hours. This matches how infrared shows up more during real sunsets. For hydroponic lettuce lighting optimization, try using IR light during the last 2–3 hours of the light cycle. It helps with growth and saves energy.

What special things should I think about when using infrared light in stacked water gardens?

In hydroponic vertical farming lighting, IR light must be spread evenly. Since plants are stacked, you need to place IR lights so they don’t cause hot spots. IR LED grow light applications often use separate panels for better control. Add airflow to prevent heat buildup from the infrared light thermal effect across growing levels.

How does infrared light affect veggies grown in water gardens?

Infrared light improves both taste and texture. Hydroponic lettuce grow lights with IR grow greens with better crispness and longer shelf life. IR light for fruiting plants boosts fruit size and flavour. Tomatoes love IR during blooming. Leafy greens respond to IR during leaf growth. Infrared light and plant growth optimization means picking the right time for each crop.

How does infrared light help plants handle stress in water gardens?

Infrared light and plant stress response are closely linked. A little IR light can help plants toughen up. It makes them better at handling heat, dryness, and other problems. IR light also helps plants make healthy compounds that boost nutrition. In hydroponics, this stress training from IR light leads to stronger, healthier plants.

How can I add infrared lighting to my current water garden lights?

Start by picking IR LED grow lights that shine at 730–850nm—those are best for plants. In hydroponic grow light wavelength setups, use IR lights that fit your plants’ needs. Let IR be 10–15% of total light at first, then adjust as needed. Some hydroponic LED lighting systems already mix IR diodes in with regular ones. Just keep energy use low while giving plants this extra light boost.

Conclusion

Infrared grow lights aren’t flashy, but they do something subtle that’s hard to ignore—they help hydroponic plants finish strong. Tomatoes flower faster. Basil leaves get thicker. Heads of lettuce? Way fuller.

Used with red (660nm) and blue (450nm) spectrums, infrared (around 730nm) nudges plants into the far-red response. That triggers a thing called the Emerson Effect—where overlapping wavelengths boost photosynthesis. It’s not magic. It’s just smart light.

And if the setup’s balanced, growers might see better yields, stronger stems, and fewer issues with slow blooming. Just don’t overdo it—too much IR can stretch stems.

Related Articles

• https://tophydroponicgarden.com/grow-lights/
• https://tophydroponicgarden.com/grow-light-penetration-for-deep-system/ 
• https://tophydroponicgarden.com/grow-light-for-leafy-greens/ 

References

1. https://plantagen.se/en/articles/tips-and-tricks/sow-and-grow/plant-lighting-facts-and-tips-about-grow-lights-and-plant-lights
2. https://www.gardeners.com/how-to/gardening-under-lights/