When you start to realize that your houseplants’ light needs may not be quite being met, it’s often a good idea to start to consider if it’s time to add some grow lights. And once you start doing some research into this, you’ll begin to find out that there are different types of grow lights for plants out there, one of the main ones being LED lights for plants. But do LED lights really help plants grow?
After all, if it’s clear that any natural light they’re getting (if any!) may not be cutting it, it’s fine to turn to an artificial solution. At the same time, it’s fair to ask the question if you’re considering buying some LED grow lights for this purpose. Alternatively, you may have looked around your house and realized that, actually, you already have some LED lights lying around.
But are LED lights good for plants? If so, what color LED is best for plants? And can plants get too much LED light – say, if they’re too close or you buy the wrong type?
Given the options on the market, it’s easy to feel like you have no idea where to start. This is why we’ll take you through what you need to consider when looking for the best light for growing plants indoors.
Do LED lights help plants grow?
LED grow lights are one of the best options for helping plants to grow. They’re energy efficient, emit low amounts of heat and are color optimized for stimulating plant growth. Regular LED lights are, however, not recommended for encouraging plants to grow as the colors are not ideal.
Basically, the color of regular LED lights are optimized for the human eye, so that they give off the white-colored light you probably recognize. To do this, the light actually involves a combination of red, blue and green LEDs, with the green acting as a counterbalance against the purple tinge.
However, as we’ll run through below, it’s actually only red and blue that promote plant growth – and it’s for this reason that using LED lights to grow plants is so effective, as they tend to be a combination of the two (even if, confusingly, the light they emit can also look white, especially if you get a full spectrum LED grow light – which you definitely should). This also means that while a regular LED light may provide some minor benefits to a plant, it won’t help plant growth as much as a LED grow light will.
Find out more about this in our article on the difference between LED lights and LED grow lights.
Here’s my pick for the best full-spectrum LED grow light for your plants:
What color LED is best for plants?
In terms of colors, the best LED light for growing plants indoors is one that has red and blue light. In fact, one reason why LED lights are good for plants is that they let you adjust the colors of the light to produce the ideal mix based on your plants’ needs.
If we go even more specific, different colors help your plants do different things. For example:
- Blue light helps your plant’s foliage become thicker. The other side of this coin is that too much blue light can make your plant compact and overly thick (which may actually be what you’re looking for, depending on the plant).
- Red light encourages blooming and fruiting in your plant, as well as promoting stem and leaf growth. This means that red light is particularly important just before your plant is expected to flower.
- Green light prompts some scientific debate regarding its usefulness but, as a general rule, it isn’t actually needed by plants. In fact, it’s why plants are green – as they reflect all green light back instead of absorbing it to help with growth.
- Yellow light also isn’t really needed for plant growth, as it doesn’t add much to its photosynthesizing.
Will plants grow under white LED lights?
White LED grow lights are very good for growing plants, as developments in their technology in recent years mean they have now become some of the most efficient lights on the market. However, a regular white LED light isn’t recommended for plant growth.
To clarify, a white LED light isn’t actually white. Instead, they’re a mix of red, green and blue. And as we’ve covered above, red and blue light are just what your indoor plant wants to thrive.
It used to be the case that white LED lights didn’t have the full spectrum of colors needed for growing plants. This is why it’s still so common to use what’s known as “blurple” lights, like these super popular ones (seriously, the reviews are crazy positive), as they can give such an intense hit of either blue or red depending on how you adjust them
However, the benefits of full spectrum white LED grow lights for plant growth mean that they shouldn’t be disregarded anymore. They’ve changed over time to the point that now, these lights emit every visible wavelength, meaning they’re much closer to the natural sunlight your plant wants (without being equivalent to direct sunlight, which may be too harsh). In fact, white LED grow lights are now often considered the best for your plants.
(Just make sure though that you’re limiting your hunt to grow lights, not regular LED lights you might keep in your home, as the latter won’t be as effective at promoting plant growth.)
By the way… if you’d rather not have plants growing under grow lights, why not check out the 23 Best Indoor Trees For Low Light Spaces (That Look Great).
Do purple LED lights help plants grow?
Purple LED lights are very effective at helping plants grow. Red and blue wavelengths of light, as found in many LED grow lights, have been found to be critical in stimulating plant growth and so using purple LED lights isolates these two colors to maximize your grow light’s benefits.
Of course, it’s often not as simple as just buying a purple LED light for plant growth, setting it up and going on your way. Instead, you may want to look for one that’s adjustable in terms of the amount of blue and red light they emit. Alternatively, you should consider your plants’ specific needs when finding one that has the right balance of each color . That is:
- To help your plant become bushier with thicker foliage, go for more blue light
- For more blooms, fruit or leaf growth, red light is better
Can plants get too much LED light?
Too much light can harm a plant and this includes if it gets too much LED light. LED lights emit less heat than other types of grow lights and so the risk of them burning your plant is low. However, if the duration of LED light a plant gets is too long, it may impact its growth.
That is, it’s important to put LED lights the right distance from your plants, which I’ll run through in more detail below. But assuming you do that, actually burning the foliage is going to be unlikely. If you’re worried, feel free to take a look at our article on signs that your plant is getting too much light.
On the other hand, given that plants need light to photosynthesize, which is critical for plant growth, many plant owners may find themselves tempted to leave grow lights on all the time – or even put them on at night when their houseplants aren’t getting sunlight.
However, in reality, plants grow faster at night as they use the darkness as part of the growth process. This means that leaving LED grow lights on a plant all the time can affect its growth cycles. While this may not harm the plant, as such, it will mean that its not able to grow as effectively as it could.
Where damage to the plant could occur is if you actually have a plant that prefers to survive without sunlight. This is why doing research into the light needs fo your specific plant is critical.
How close should LED grow lights be to plants?
LED grow lights should be placed between 12 and 20 inches (30cm to 50cm) away from the plants. This will ensure that the plants are close enough for the light to reach them while not being so close that there is a risk of damage to the foliage.
That said, it’s not an exact science and so if the lights are slightly closer or slightly further away, it should be fine. You should also check the wattage of your specific LED grow lights as a higher wattage (of about 1,000 watts or higher) should be placed closer to the 20 inch mark rather than the 12 inch mark.
Remember: This guideline is for LED grow lights for plants. Other types of grow lights, like fluorescent ones, emit more heat and so it’s more important to be aware of their distance from your plants to avoid burning the leaves or overly drying out the plant.
What kind of LED lights grow plants?
The kinds of LED lights that grow plants vary depending on the exact amount of each wavelength you choose, which will depend on what’s known as the “color temperature” of the light you use. These temperatures include:
- 2700K: For when you need more red light for flowering – Lower color temperatures mean warmer light with more red wavelengths. For example, these white LED 2700K bulbs are described as “warm white” for this exact reason. Just be careful, as too much red light can cause your plants to stretch and weaken.
- 3000K to 3500K: For when you want a light for every stage of growth, including flowering – These are slightly cooler than 2700K but will probably be better for someone who wants to not just focus on one stage of the growth cycle. This pack of 3500K natural white LED bulbs would be perfect for this.
- 5000K to 6500K: Good for growing vegetation – While 5000K LED will grow plants, choosing something in this range means your main focus isn’t on encouraging your plants to flower. 5000K white LED lights, like these, are going to be enough for most people unless you really don’t want to do anything else, in which case you may lean more towards choosing 6500K.
FYI: This is why, when looking for which light to buy for your houseplants, it’s not enough to simply check a white LED grow light review and know what you’re getting. You have to also be sure that the color temperature aligns with the type of plants you plan to grow and what you aim to get out of them.
That’s also why we consider this adjustable, full-spectrum LED grow light that I mentioned earlier as the best choice for most indoor gardeners, as it gives the full range of options depending on what your plants need at any specific time.
What kind of LED grow light is best?
The best LED low light for you is the one that responds best to your plants’ needs, which will likely have blue and red wavelengths. This means that you should look for one that has the most appropriate color temperature depending on whether you are focusing on flowering or vegetative growth.
A great option to allow for the different stages of your indoor plants’ growing cycle is to get an LED grow light that you can adjust. This means that if, say, your plants are close to flowering, you can make the light warmer to encourage this. It’s also good to get an LED grow light where you can adjust how long they’re getting light for.
My preferred LED grow light has all the features you’ll need, including:
- Full color spectrum, meaning you can choose the color temperature of your light
- Automatic timer, so you can have your lights on for four, eight or 12 hours depending on things like how much light your plants need and whether they’re getting any natural light as well
- Dimmable light levels, allowing you to turn down the brightness if your plants don’t need quite as big a spotlight on them
- Extendable stand, meaning you can make it as tall, short or in whatever direction you need based on the room your plants are in
- Remote control adjusted, for those looking for something where you don’t actually have to get up to look after your houseplants
Can you use LED strip lights to grow plants?
You can use LED strips as grow lights as long as they’re bright enough to reach all your plants. They’re also better for vegetative growth as the light from LED strip lights probably won’t be enough to encourage your plants to fruit.
However, they can be a great option for anyone looking to simply grow some smaller pot plants or if you don’t have much space for a larger grow light set up. They can also look amazing when put under a shelf to light plants on a surface below, as they basically look like downlights.
In terms of which exact ones to pick, these LED strip lights have incredible reviews. People mention how they’re super affordable, easy to mount and have just the amount of light that plants need.
To see a full review of these, including to see how they look once they’re mounted, take a look at this video which involves someone talking you through these same exact LED strip lights:
Final thoughts on LED lights helping plants grow
Almost every indoor gardener can benefit from using LED lights to help plants grow. Unless you live somewhere that consistently gets solid amounts of sunlight, there’s no question that LED lights are good for plants that would otherwise suffer from their light needs not being met.
And while you may be tempted to use that LED light you already have at home (or one you saw at the store for much cheaper than an LED grow light), your plants will respond to much better if you use an LED grow light instead.
And then it’s on you to figure out fun stuff like the best color temperature based on which plants you have, your plants needs, how they’re positioned…
There’s no one-size fits all answer, which is why we prefer to recommend that when looking for an LED light for plants, it’s going to be better to buy an adjustable LED grow light. That way, your light can adjust as your indoor plant collection does too, making sure that it can continue to thrive.