INDOOR LIGHTING GUIDE: All you need to know for lighting your carnivorous plants indoors

Macodes

Sprout
the info on these forums has helped me quite a bit, so I felt its time to contribute.

This guide should help you in purchasing the right light for your plants.
I know there is a lot of info out there about lights, but most of it is scattered about. I wanted to write this all-in-one guide for the forum, If you came in knowing nothing and read everything I have written here you will have enough knowledge to purchase a proper light for you plants.

***IF you only want to know which LED to buy and don't care about the finer details scroll down to the last bolded section: "LED BUYING GUIDE"
I do also recommend reading the section "How much PPFD do I need? (for carnivorous plants)"

BASICS
Measurements for how "good" a light is:

The only real measurements that matter are PPFD and wattage. Everything else is useless when it comes to plants. knowing measurements like lux and lumens or whatever else is worthless. Its the equivalent of asking the color of a car to determine the speed. Spectrum, or the color temperature of light matters as well.

what is PPFD?
PPFD stands for Photosynthetic Photon Flux Density it is sometimes called something else like PAR, but as long as the units are µmol/m^2 s it means the same thing
What does this mean and why is it important?
PPFD measures how many light particles (aka a photon) useful for photosynthesis hit a particular sized surface per second. Since we are growing plants we really dont care about photons that are not useful for photosynthesis.
It generally uses units of µmol/m^2 s
the "µmol" is just the count, literally the number of photons so 1µmol is 6.022 x 10^17 photons
"m^2" is the surface size which in this case is just one square meter
"s" is the time in seconds
So most PPFD measurements will tell you how many µmol of photosynthetically useful photons hit a square meter per second.
When it comes to growing plants we really do not care much about other types of photons.

How much PPFD do I need? (for carnivorous plants)
Direct sunlight is approximately 900-1500 PPFD, most prefer to have a longer lighting period and lower PPFD. I personally wouldnt go below 200 PPFD
I am mostly interersted in Nepenthes and pitcher type carnivorous plants so that is what I will write about.
There are many articles on PPFD requirements but I really liked the focus and format of the one written by Andrej Pavlovič et al.
(link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2710902/ )
Although it is on Nepenthes talangensis, I would predict that most Neps, and carnivorous plants (pitchering ones at least) in general would follow a similar trend.
A. Pavlovic et al. looked at what the cost of producing a pitcher is, and the PPFD that would be required to make the cost of producing a pitcher worthwhile for the plant.


7883

figure 3 from Andrej Pavlovič's article "Feeding enhances photosynthetic efficiency in the carnivorous pitcher plant Nepenthes talangensis"

In the above graph. The "Cost" line is the cost of producing a pitcher for your plant. If the benefit is below the cost then it is not "profitable" for you plant to make pitchers. We want anything above the Cost line so that your plant can actually benefit from its pitchers. In this case a little below 200 PPFD is the break even point. It is also interesting to see that after the 600 PPFD mark there is little growth in benefit.

Why is wattage important?
The wattage is used to determine the PPFD/watt, higher PPFD/watt means more efficiency which is better.

What about spectrum and color temperature?
The spectrum is the component wavelength or color of light are being emitted by the light. Color temperature is in units kelvin and just helps to roughly describe how warm and red or cool and blue a light is to our eyes.
Different wavelengths and colors MAY have different effects on you plant. It has been shown that warmer reddish lights promotes flowering, and cooler blue lights promote vegetative growth, but to be honest I am not sure if there has been any significant studies in terms of spectrum and carnivorous plants nor if this was ever quantified in a significant way.

TYPES OF LIGHT:
Metal Halide, High Pressure Sodium (and all other large high wattage single bulbs):
Efficiency:
around 1.3 ppfd/watt
pros:
-good spectral output.
cons:
-Generates a lot of heat
-requires regular bulb replacement
-Expensive, especially for the performance.
Comment
These bulbs are decent, and before the advances in LED technology, it was the best light you could get. It will still work but it is better to transition away from these if you can. Put it this way, you can still use a old flip phone, it will definitely work, but why not just get a smart phone its not much more. To me these lights are the flip phones of the plant lighting world.

Flourescent (T5,T8, bulbs etc.):
Efficiency:
less than 0.7 ppfd/watt
pros:
-Nothing.
cons:
-requires regular bulb replacement
-extremely low efficiency
-terrible penetration depth
-expensive in the long run
Comment:
There really is no reason to use these anymore. Please get rid of them, let the market die out these bulbs are just plain bad for your plants, the environment and your wallet. Its only use is if you require UVB (generally used for reptiles).

LED
Efficiency:
Extremely variable, you can get ones as bad as T5, and there are some LED that around the 2.2+ ppfd/watt
Pros:
-long life span (in the range of a decade)
-excellent penetration depth
-focused spectrum
-newer models produce very little heat
-Much better efficiency than any other type.
-cheapest light solution in the long run.
Cons:
-none I can think of
Comment:
A couple of years ago, LED weren't that good, but the recent advancement now put them ahead of all other options.
this is the future of plant lighting. LED's will only become more efficient while other technologies will die out. I recommend switching to this.

LED BUYING GUIDE:
- Check the PPFD rating, I personally would not buy an LED if it did not have a detailed PPFD rating, greater then 200 PPFD should be sufficient. but higher is better.

-Be careful about PPFD ratings, many manufacturers take the measurement in a reflective box which drastically inflates PPFD values, Since our hobby is more aesthetic focused as opposed to efficiency most of you probably wont use reflective boxes. Also take in to account the height the measurements are taken. Be very careful about the PPFD numbers, and read the fine print.

-I generally do not trust LED lights that do not have PPFD measurements. The better and more honest manufacturers will show a plot of PPFD variance across some surface, the distance from the floor to the light, and the conditions of their measurements, whether it is in a reflective box or not

- determine the wattage and calculate the PPFD/watt, just divide the PPFD and the watt, higher is better. You want to try to get around the 2 PPFD/watt range. Anything below 1.5 PPFD/watt than your not really taking utilizing the advantages of LED technology

- Please please please DO NOT buy those blue purple, blurple LED lights. You cannot enjoy your plants under the light, you cannot see their coloration, it will give your room an obnoxious color, and they do not have any more PPFD than a neutral white light. If someone gave this to me for free I wouldn't even take it. They just defeat the purpose of the hobby for me. You wouldn't go to an art gallery with sunglasses on would you? I like to treat my plants like art.

-gravitate to more neutral color lighting. Although it is unsure how a more red or blue spectrum effect the growth of carnivorous plants I do feel that more neutral lighting looks better when viewing plants. I feel that cooler lights give a weird bluish tint to everything under it and warmer lights give a off reddish tint to everything.

-try your best to get UL, ETL certified lights, this is more for insurance purposes, and if your house burns down because of a light. LED lights are quite simple in their construction but it never hurts to be safer if possible.

-Newer LED lights will generally have many small lower wattage LEDS on a surface if you can try to get these lights. They have a more even light dispersion, and generate less heat.

-A few years ago High wattage single LEDs were really popular but the issue is they generate a lot of heat. So similar efficiency and PPFD as newer models but with more heat. When I say heat, I mean enough heat to cook an egg on. Some get extremely hot. I am surprised some units More heat means more potential for fire, because of this I would not buy one of these high power led unless it had ETL/UL certification. Try to avoid these if you can.

-Newer boards mostly use LM301B, I believe this is the most efficient LED on the market currently not 100% sure though. It does have great reliability.

Thanks for reading hope this helps!
I will probably write more guides like this to help out others in the hobby. Most of them are just my personal notes anyway.
The next thread I will do will probably be how to fully automate any setup including cooling for highland Nepenthes. what parts, boards and sensors to get. I will also probably make a git repository for it so you can just plug and play to use it right away. If I am not feeling lazy I may even make a UI for you phone so you can monitor it.
 
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Nice writing.

Can I compare the PPFD of my 2X4 T8 setting with my 2X4 LED setting ?
T8 is probably closer to 0.4 ppfd per watt probably less. These are extremely inefficient. Not to mention they are bad for the environment and also have mercury.

To calculate for a rough estimate multiply the number of total watts of all the bulbs by 0.4 that should give you a rough (more generous) idea of ppfd

If your led is from a more recognized established manufacturer you can look at their specs for ppfd. If they didn't put anything it's likely going to be quite low, but really it's a crapshoot

It will probably be pretty low. It's sad because most t8 and t5 fixtures and lights are quite expensive and then you go to IKEA and get a cheap $10 grow light and it has almost 3x the ppfd efficiency
 
T8 is probably closer to 0.4 ppfd per watt probably less. These are extremely inefficient. Not to mention they are bad for the environment and also have mercury.

To calculate for a rough estimate multiply the number of total watts of all the bulbs by 0.4 that should give you a rough (more generous) idea of ppfd

If your led is from a more recognized established manufacturer you can look at their specs for ppfd. If they didn't put anything it's likely going to be quite low, but really it's a crapshoot

It will probably be pretty low. It's sad because most t8 and t5 fixtures and lights are quite expensive and then you go to IKEA and get a cheap $10 grow light and it has almost 3x the ppfd efficiency
 
Something to note: I recently had to buy a new electronic ballast for my T5HO fixture. Cost ~ $50 for a 2 bulb one. So that's an extra cost for fluorescents.
 
Hello. Thanks for the informative lesson.
I am new and still confused. But I got a noma LED light, with 1600 lumens. And leave it on 12+ hours. My vft is growing. I'm still obsessing I guess. Any thoughts?
 
Hello. Thanks for the informative lesson.
I am new and still confused. But I got a noma LED light, with 1600 lumens. And leave it on 12+ hours. My vft is growing. I'm still obsessing I guess. Any thoughts?
hey Ryan. I'm kinda new also. a year in or so.. I was overwhelmed when I first started looking into lights. asked alot of questions and doubted myself. some people have crazy setups for lights and others dont. like @Lloyd Gordon said they are fine. ..... I grow indoors and my set up consist of T5 and T8 LED grow light from barina - 24" . I got them on amazon. my plants are growing great and have tons of colour. the high end strong ones I'm sure you can keep further away. mine I figure are on the low end so I keep them closer and use 1, 2 and 4 bars per shelf, . I keep them on for 14hr ..not sure the par or ppfd but the watts range from 24 - 48 hanging about 10" - 24" above pots .. hope that helps comparing to your setup and ..
 
Thanks #stini. T5&8 are large lights?
so I got these two in yellow- 2ft. link below. yellow looks better then the pink and pinkish white. some people use white shop light (LED) as well . they are not big at all .. I waited till they went on sale.. I'm happy with them.

the two big VFT on the top are a year old ??? maybe less and I put them into dormancy this past winter. sooo bouncing back strong. they are from Loblaws. lol. the two on the right I got a few weeks ago from a person, still adapting and starting to put out new traps. they are small and I'm feeding them bloodworms. I soak them in distilled water first.

you cant see the lights. they are flush under the racks

racks are 30" wide I think +/-

pic with mixed CP's
- top shelf has 2 T8 (might add more T5 to it I have extra )
-mid shelf has 2 T8
- bottom shelf has 4 T5

Pic with Neps
- top and middle have 1 T8
- bottom has 2 T5


IMG_6805.jpg

IMG_6806.jpg





https://www.amazon.ca/Barrina-Spectrum-Equivalent-Greenhouse-Installation/dp/B07V6YJKR6/ref=sr_1_6?crid=3OVPOARQWSIHQ&keywords=barina+grow+light&qid=1683596125&sprefix=barin,aps,143&sr=8-6&th=1

https://www.amazon.ca/Barrina-Equivalent-Spectrum-Integrated-Growing/dp/B082ZL2L3N/ref=sxts_b2b_sx_reorder_acb_customer?content-id=amzn1.sym.1ddccd64-a673-406b-92f9-43f98e735ccb:amzn1.sym.1ddccd64-a673-406b-92f9-43f98e735ccb&crid=3OVPOARQWSIHQ&cv_ct_cx=barina+grow+light&keywords=barina+grow+light&pd_rd_i=B082ZL2L3N&pd_rd_r=0b952e91-a0ed-4ac9-a44b-1aa51ed24fb0&pd_rd_w=NefhN&pd_rd_wg=qoVlV&pf_rd_p=1ddccd64-a673-406b-92f9-43f98e735ccb&pf_rd_r=YJ148FQHZ4F4JDSGKP85&qid=1683596125&sbo=RZvfv//HxDF+O5021pAnSA==&sprefix=barin,aps,143&sr=1-1-62d64017-76a9-4f2a-8002-d7ec97456eea
 
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