Over the years, I’ve responded to hundreds of emails from readers. By far, the topic you emailed me about most is grow lights, specifically, LED grow lights and which ones you should use. A good grow light can be a game-changer when it comes to growing plants indoors, whether that be houseplants or seedlings for your garden.
So, let’s take a look at the three most important features to look for in an LED grow light.
My How Things Have Changed
A few years ago, I wrote this piece. It’s about the influx of inexpensive LED grow lights that flooded the market and how the lack of regulation made it difficult for consumers to distinguish the good from the bad with all the marketing fluff.
In the same piece, I discussed the different types of light in the electromagnetic spectrum and how plants use each color of light. I stressed the importance of choosing an LED that provides the light colors plants need (PAR). (It’s still worth a read for this information.)
I finished by lamenting that, at the time, I couldn’t give a solid pick for “the best” option because marketers weren’t providing the information needed to make informed buying decisions. They were all obsessed with wattage, which doesn’t mean a whole lot when you’re talking about an LED grow light.
Since then, I’ve tried quite a few LED grow lights.
For once, the market did what it’s supposed to do – better products outcompeted the poorer ones. Better options emerged, and manufacturers started providing the information that is actually important when choosing a grow light. Amazing!
In the end, I found a brand I love (my plants do, too), and I’ve stuck with it.
I’ll share that brand in a bit, but I don’t want to assume that you and I want the same things when looking for an LED grow light. So, I’ll provide the essentials to look for when choosing grow lights.
(If you’re looking for a high-quality, affordably priced grow light, no matter your setup, then by all means, please skip this part and scroll to the bottom for my recommendation.)
The Three Most Important Things to Look for When Choosing LED Grow Lights
A caveat: My advice is meant for the average home gardener or houseplant parent, not the professional grower with a large-scale setup. Your needs will likely be much different.
I’m only going to talk about LED lights here because they’re what everyone generally uses these days. LED grow lights are much more energy efficient, which means they cost less to run. Because they use less power than traditional fluorescent or HID lights, LEDs also don’t put out nearly as much heat. This makes LED grow lights the light of choice for most of us.
I’m not going to discuss size or shape or whether you use strip lights or a bulb. You know your situation and what will work best for you. I’m only equipping you with the information needed to make sure you get a quality light that’s going to help your plants.
Let’s jump in!
What Colors Does the Light Emit?
This is easily the most important consideration when choosing an LED grow light. Light is measured and categorized by its wavelengths on the electromagnetic spectrum. The different wavelengths of light allow us to perceive different colors. For example, 630-660 nanometer wavelengths of light are perceived as red. 400-520 nanometer wavelengths are blue, and so on and so forth.
It seems kind of obvious, but plants do best with a grow light that mimics natural sunlight.
LED grow light manufacturers got really hung up on red and blue light because plants use those two colors for flowering and leaf production, respectively.
However, years of research aboard the International Space Station showed that plants need and use nearly every color on the light spectrum, but in varying degrees and at different times over the plant’s growth cycle.
Choosing one light color over another can cause deficiencies in your plants over time.
When choosing a quality LED grow light, look for a “full spectrum” light. This will provide your plants with the different colors of light they need, including red and blue.
PAR – Photosynthetically Active Radiation
You may see the acronym PAR in the description of a grow light. PAR refers to the range of light wavelengths (on the electromagnetic spectrum) that plants use for photosynthesis. The range is typically between 400-700 nm. The larger the range, the more light colors usable by plants the grow light emits. If you’re buying full-spectrum lights, then you’re getting the full range, so you’re good to go.
Light Intensity
The intensity of an LED grow light is also an important consideration, and no, I don’t mean watts. When we talk about light intensity, we’re looking at how much PAR (usable) light reaches the plant’s surface per second. This is called PPFD (Photosynthetic Photon Flux Density).
All you really need to know is that the higher the PPFD, the more usable light there is available for photosynthesis.
Higher PPFD means your plants will have more energy for growth and things like flowering and putting out fruit.
Keep in mind that PPFD can be increased or decreased depending on how close the plants are to the grow lights. If you buy a high PPFD light but place it too far away from the plants, then it won’t be as effective.
You can dial in the PPFD of your grow lights by moving plants nearer or further away from the lights or adjusting the light height. This brings us to the final important factor to consider when choosing an LED grow light.
Light Coverage Area
The coverage area refers to how much space a grow light can adequately cover. This is really important to keep in mind when choosing a grow light to fit your space. You need to ensure that all of the plants under it receive sufficient light.
A grow light may be sufficient for a small, concentrated area but may not effectively cover a larger space. For instance, I put small 12” long grow lights under my kitchen cupboards. (Seriously, it’s the best thing I’ve done for my kitchen.) The plants sitting directly beneath them receive the highest PPFD; the plants further out to the sides receive less.
That’s not a bad thing!
It just means being mindful of which plants need more or less light. I like to keep my African violets directly under the grow lights to keep them blooming constantly, and my kitchen herbs hang out on the sides of the light.
Most manufacturers specify the coverage area of their grow lights.
Consider the size of your grow area when selecting a light, and make sure the light can cover the entire area evenly. For larger spaces, you may need multiple lights to ensure adequate coverage, just like I did beneath my kitchen cupboards.
To ensure my little countertop garden is well-lit, I installed two rows of grow lights instead of one.
With these three factors in mind, you’ll be able to find quality grow lights that will meet your plants’ needs. But if you don’t want to mess around with searching, I can recommend some pretty great grow lights.
My Favorite Brand of Grow Lights
In fact, they’re the only ones I use. Whether it’s in my basement grow tent for seedlings, propagation and winter gardening or the ones around my house for my houseplants, I’m continually impressed with Barrina brand grow lights.
They are all full-spectrum and high PPFD, so there’s no need to worry there.
Barrina grow lights are powerful, easy to set up, lightweight, and won’t break the bank.
Each set comes with everything you need to hook them up and hang them. The T5 and T8 lights can be daisy-chained together (cords included) if you’re putting them on multiple shelves or need more than one light for good coverage.
Barrina always includes plenty of hardware that allows you to hang the lights in multiple ways, including renter-friendly options like sticky tabs.
They offer both T5 and T8 lights for hanging and even have standing grow lights, which are popular among houseplant lovers. They recently introduced puck grow lights, which would be great for adding to shelves. (I’m currently making room on my bookshelf for these and more African violets.)
One of my favorite things about Barrina’s LED grow lights is that despite being full spectrum, many of their lights come with three color options: white, yellow, or pinkish-white. I like choosing yellow or white to use around my home so they blend in with the other lighting in my house.
I’ve bought many cheap, awful LED grow lights over the years.
All of them ended up being donated to Goodwill when I bought my first set of Barrina lights in 2023. The difference in the light quality and the health of my plants was almost immediate.
They are the only grow lights I use. And that first set is still in use and still going strong.
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