We decided to do an experiment. We’ve already talked about the challenges of finding the right grow light, especially when there’s an insane number of brands out there, each with its own “correct” information. We see on almost all product pages we browse on Amazon; claims about most efficient, highest performing that. Most of it sounds great to the trusting and confused first time grower. Let’s iron out the facts.

Experiment/survey

We contacted six different brands that all sell similar types of LED grow lights on Amazon.

We asked them all the same questions (see further down).

We did not engage in a discussion or ask follow up questions.

Our goals

Test brand’s responsiveness.

Understand how much the brand knows about their product.

Understand how much the brand knows about growing.

Get an impression of their origin and way of handling queries.

Compare different brands.

The test

Five of the six sellers were contacted around 8 am PST on a Friday. Amazon put a limit to how many messages we could send at once so the sixt seller’s message was sent a few days later.
We created a scenario that is typical for beginner/first-time growers and asked six questions that are relevant to understand a lamp’s performance in order to successfully set up a grow space.
We selected six manufacturers that we’ve seen on various places online: Amazon, forums, social media, blogs, etc, and sell a fair number of lamps to beginner growers. We chose a lamp these brands were offering that cost between $140-180. A cheaper/smaller lamp would most likely not perform anywhere close to satisfy two mature plants.

Following message was sent:

I’m looking for an LED grow light for my small scale indoor cannabis grow project. I will be growing two plants and I expect them to occupy about 3×2′ in total.

I’m looking at your grow light model XX but I’d appreciate it if you could give me a bit more info about it.

• Would you recommend this grow light for two plants? Would I need more than one lamp to cover the 3×2′ area with light?

• Do you have a light footprint map for this lamp?

• What’s the lamp’s efficacy?

• What color spectrum does it emit?

• What wattage of diodes are you using and why did you choose these?

• What does the warranty cover?

Hope to hear from you soon!

Brands & products contacted

Exlenvce: Rank 1 for “LED grow light”:

Mars Hydro: Talked about grow light brand on forums

Phlizon: Highly ranked and popular Amazon brand

Viparspectra: Highly ranked and popular Amazon brand:

LEDTonic: Talked about grow light brand on forums

BESTVA: Talked about grow light brand on forums

Here are their answers

EXLENVCE

I hope all’s well in your world, and you’re having a stellar day ,
“This is Susan from Customer Support Team, Thank you for your attention to our brand and hope you can become our customer.
I am very happy to answer your all question.

1) Would you recommend this grow light for two plants? my answer :   I highly recommend it for you plants, I am sure your plants will love it.

2) Would I need more than one lamp to cover the 3×2′ area with light?  my answer : one light enough, We recomend you buy 1200w enough, you can save 30usd

3) Do you have a light footprint map for this lamp?  my answer : You can find the photo on our webstie , the last photo.

4) What’s the lamp’s efficacy? my answer : The lamp can help your plant share sunshine indoor.

5) What color spectrum does it emit?  my answer : The lamp include red, blue , white, orange, UV, IR, wavelength 370-750nm

6) What wattage of diodes are you using and why did you choose these? my answer : All 150w leds Power total Consumption: 260W , Our led is Triple-Chips  

7) What does the warranty cover?  my answer : we supply 4 years warranty.

Please contact me if you have any question, I look forward to hearing from you again.

Susan”

420LED’s comment:

Responded in 14 hours.

Weak reply showing no in depth knowledge about neither light or growing. While the lamp draws 260W according to the manufacturer, its light output (PAR/PPFD) is rather low and it’s spread is only shown in a 2D model making it (at best) difficult to assess if it indeed covers the necessary area with high enough light intensity. They do not have a website but what I think she’s referring to is their Amazon product page.
Does not answer the question about efficacy at all but diverts or plainly talks about something different. Our question about the color spectrum is also poorly answered with no reference to an actual spectrum.

About the diodes, she says they are 150W each. Likely a typo and should be 15W, which is a rather inefficient size. “Triple-chips” means nothing.

Unclear what the warranty covers.

Overall impression: Lacking attention to detail, likely Chinese, few direct answers, does explain the product well enough to fully understand its performance.

420LED rating: 2/5

MARS HYDRO:

“here are the answers to your questions:

1. the coverage of this light is 3*3 ft, therefore, 1 lamp is suitable for your plant growing.
2. perfect 250W HPS grow light replacement, ensure 40% energy saving, and fix the HPS’ heat problem properly.  
3. spectrum: 440nm, 460nm, 630nm ，660nm,730nm(IR), 2400k-3000k.
4. Actual Wattage at 110V: 161.7W±5%;  Actual Wattage at 220V: 158.4W±5%
5. warranty policy:

to repair center:

within 1 year, we cover the shipping and repair charges.

from 1 to 3 years, you cover round-trip shipping charges, repair charges and handing fee.

repair by yourself:

within 1 year, the replaced parts and shipping are free. From 1 to 2 years, you’ll be responsible for shipping charges and replaced parts are free. From 2 to 3 years, you’ll be responsible for shipping charges and handling fee.  

hope this is helpful for you

jay”

420LED’s comment:

Responded in 12 hours.
Gives no information what the coverage estimate is based upon, no PPFD/PAR values. Skips the question about light footprint map altogether and instead references something irrelevant.
Explains what wavelength of diodes they use but not what spectrum they emit. Based on the product detail page, it’s almost exclusively blue and red. Does not answer our question about the diode size and offers a DIY warranty.

Overall impression: Similar to previous brand, very short, non specific answers. Vague and noninformative with little value that could be practically used. Chinese brand.

420LED rating: 3/5

PHLIZON
(email was send few days after all others).

“Thank you for your email.  

1. This 1200w grow light may be a little small for your 3*2ft growing area. If you want a professional grow light, we highly recommend you our professional 2000W CREE cob grow light, which has higher PPED value and higher actual power. And it will fit for your plants perfectly.  
2. i am so sorry that we don’t understand your meaning. Do you mean the PPFD value of the  footprint map

3.The actual power of the 2000w cob is 451watt

4.All our grow light is full spectrum which can serve your plants better.  

5.For 2000w cob grow light ,we use CREE cob led and 10w led .  

6.Our warranty time is 2 years.  

Thank you very much and if there is any question , please don’t hesitate to contact us.” 

420LED’s comment:
Responded in 16 hours.

Despite saying that the lamp suits a 3×3’ space in the listing, they now say that the lamp is not enough for a 3×2’ and instead recommend a larger lamp. No data given for the lamp’s efficiency and the reply does not answer any questions about the lamp I inquired about but only goes on about the other lamp they suggest. They claim their lamps have full spectrum but as their listing image shows, the spectrum almost entirely consists of only blue and red.

Our overall impression: Again a rather inconclusive reply where not much useful information can be extracted and I find little reassurance that the lamp would perform well. The seller writes okay in English but is obviously from China.

420LED rating: 3/5

VIPARSPECTRA

“Thank you for contacting with us.

As for 3×2′ area, if you wanna to provide full coverage to the grow area, one 600W light would be OK. The 600W light is perfect for a 3’x3’ vegetative coverage at 32” and 2.5×2.5’ flowering coverage at 22”.

I click on the link you provided, it turns into the detail page of our V900 light. The V900 light comes with optimal full spectrum which is ideal for a 4×4’ vegetative coverage at 32” while 3×3’ flowering [e-mail address removed]s that it’s a little big to 3×2′ space, do not need another light to vover the 3×2′ space. The actual power draw of this light is 390W, while Amperage is 3.55A at 110V. More other details, you could kindly refer to our detail page.

Finally, all of our led grow lights come with hassle-free 3 years US local warranty, plaase do not to worry. Enclosed some pictures for your reference, you could have a check it.

If you have any concerns with this regards, kindly let me know. We are pleasure to help you!

Have a great day:-)”

420LED’s comment:

Responded in 20 hours.

Friendly approach and suggest a different product than inquired about but without any supporting facts documents. Only answers our first and last question, which is always a cause for concern. Provided a light footprint map that showed the lamp’s PPFD/PAR values at once distance, 28”. Center spot value reads 480 PPFD while values at 2ft are around or between 160-318 PPFD which is rather underwhelming.
Seems to offer a comprehensive warranty.

Our overall impression: Since so few questions were actually answered, that is the most significant takeaway from this brand in my opinion. The light footprint map and the warranty were positive inclusions but one distance on the footprint map makes it difficult to fully understand how the lamp performs. The grammar in the message suggest that also this seller is from China.

420LED rating: 3/5

LEDTonic

“Thanks for reaching out. Is this your first grow or have you grown before? Perhaps with other LED lights or HIDs?

We recommend our Z5 grow light for 2×2′ spaces. Some growers fit two plants perfectly fine into that space, other growers, as you mentioned, require a little bit more space for two plants. The Z5 has a good reach over a 2×2′ area but would lack a bit for a 3×2′. If this is your first grow, your plants will likely not be limited by the light but rather other aspects like plant management, nutrients, temperature, etc. No one gets everything right on their first grow. My point is that if this is indeed your first grow, you’ll do OK with one single Z5 for your two plants, especially if you use reflective (mylar) walls around the plants. However, if you’re an experienced grower and you have already mastered all aspects of indoor growing then you may want to consider some kind of additional light to complement the Z5 for the 3×2′ space. Hope this makes sense to you.

Yes, we do have a light footprint map with PPFD values available. It’s among the images in the listing but I’ll attach the file to this email as well. We’ve measured the PPFD values at 12″, 18″ and 24″ with an MQ-500.

The Z5’s efficacy is 1.3 umol/J.

We have a balanced and full spectrum. While it appears pink to the naked eye, i.e. it’s a bit dominant with red color, it still covers all colors of the spectrum well. As per the attached image, you’ll see that the light distribution is ~63% red, 18.5% green, and 18.5% blue. We’ve chosen this specific configuration as it is in line with what experts in the field recommend. Plants want all colors, including green (to some extent).

The diodes are 3W each and we push them to about 58% of their maximum capacity, i.e. 1.75W each. They perform well at this rate and the heat they emit is efficiently dispersed by the heatsink these diodes are fixed against.

Contrary to what other brands claim, the larger the diode (i.e. 10W or 15W) the WORSE is their efficiency. Feel free to confirm this on other sources online.

Our 3-year warranty covers the entire lamp. Any and all internal components are covered. No matter what fails, we’ll fix it. The only thing you should take into account that diodes, all LEDs, have a natural deterioration rate. This is typically affected by the quality of diodes and how warm they and their surrounding is. If the working temperature inside the housing exceeds 120F, diodes deteriorate quicker than normal. This is why we’ve chosen to use a heatsink inside the lamp. Although this natural deterioration occurs, it’s still fairly limited. After 50.000 hours, the diodes will still operate at 70% of their original performance. That’s 8.5 years if the lamps are on every day for 16 hours.

Let me know if you have any further questions, we’re always happy to talk about anything indoor growing related :-).”

420LED’s comment:
Responded in 4 hours.

Long response covering all of our questions in detail. While this seller’s lamp provides the smallest coverage area, it is still illuminated the best according to the light footprint maps provided. The seller also explained how the PPFD/PAR values were measured and provided a light footprint map for three distances which should be used for early veg, veg, and flowering.

Does not talk about what wavelength of diodes they use but rather the ratios of each color supplemented by a spectrum chart. Seems to have both good size of diodes fitted on the lamp and also offers a warranty that covers the entire lamp.

Our overall impression: All questions answered well and in detail. Talks extensively about some topics and tries to explain both how to use the lamp but also how it performs. The seller sent both a clear light footprint map and also a spectrum chart showing the lamp’s stats and performance. Seems to know both the product and how to use it very well without over-selling or over-promising. Appears to be American/European.

420LED rating: 4/5

BESTVA

“The light perfect for a 6.4′ x 6 growing area at 24” height.

And we use Dual-chip(10W) LEDs which is much brighter and more efficient than traditional 3W and 5W LEDs. It is the HIGHEST PAR/LUMEN OUTPUT PER WATT.

If your plants are big ,we suggest you need one more lamp.

Because the plants need more PAR. and the Full Spectrum is as attach show.

We have 3 years warranty. If there have any question ,please feel free to contact us.”

420LED’s comment:
Answered in 12 hours.

Claiming a 6.4×6’ coverage area with a lamp that is far from square is the first warning sign. Looking at the light map available in the listing also suggests that the lamp should MAX be used in a 4×4’ area but even this is highly questionable as the PPFD/PAR values are only provided in two directions. 10W chips are NOT the most efficient out there, far from. Once again, misinformation and lies. If the theory of “the larger the better” diodes would be true, why wouldn’t they use 15W? But once again, it’s the opposite that’s true: the smaller the better.

Did not attach any document, does not very well explain what the warranty covers.

Overall impression: The most inaccurate and misleading answers among all of the surveyed brands. There’s not one good takeaway from this seller and nothing he said suggest that the product will perform well. Clearly a Chinese seller.

420LED rating: 2/5

Final Conclusion

As suspected, the majority of brands out there are Chinese and provide inaccurate or lacking information for the most part. Viparspectra seems to be more on point than other asian brands but still the information provided is lacking. No one but LEDTonic addressed the question with efficacy which is a key performance indicator. With LEDTonic’s exception, all brands provided incomplete answers to our questions where BESTVA gave the least satisfactory answers.

We suggest you do a similar test when deciding which brand you want to use. While price can be an important factor if you make your decision on that alone you can clearly end up with a lamp that is nowhere close to what you need.

If you’d like us to do a similar follow up test with other brands, please comment below and once we have a decent list, we’ll get to it.