PAR for Plants - Lumens for Humans

While the lumens measurement is based on the sensitivity of the human eye to light, PAR Watts objectively measure the total watts of Photosynthetically Active Radiation (PAR) emitted by the lamp. It accounts for the nutritional value and is a direct measure of light energy available for all-important plant photosynthesis.

Author: Mr.Zog

How much PAR does a plant need?

I'm with the lasty guy, What PAR do plants need and when?

I'm with the last two guys. How much PAR does the plant need and how much is optimal?

Think I found an answer in another thread in a post by Icemud:

Possible to have too much light?

Sorry, sick for awhile. so I couldn't respond. So the post you're referring to has this:

"So generally if flowering in a 12/12 schedule you want to see at least 510 micromoles PPFD
optimal is 800-1100 micromoles PPFD without added CO2 800 - 2000 micromoles PPFD if supplementing CO2.

This is only for 12/12 schedules, if using 18/6 or another light regiment, then these numbers change based on the length of daylight."

OK, yes thats an answer of sorts, a little technical and confusing without more research. Here's what I get out of it all:
PAR = Photosynthetically Active Radiation = basically the range of light spectrum that plants use for photosynthesis
PPFD = Photosynthetic Photon Flux Density - the measurement of PAR
micromoles = basically the unit of expression of PPFD or the photons falling each second per 1 square meter of area at the plant canopy level.
So in short the PAR he's suggesting is 1100 micromoles per second per square meter, try to find that information on any light anywhere!
I don't really think that helped much.
Try this site:
https://www.---------.com/community...-a-lot-of-other-lighting-spectrum-info.37783/
It's a very good explanation of all of the different measurements, units, terms and how they all apply, or not, to plants.

Stay Medicated,
devolving

devolving said:

So in short the PAR he's suggesting is 1100 micromoles per second per square meter, try to find that information on any light anywhere!

Click to expand...

You're right, that information from vendors is rarely available but I have seen it a couple of times. I have also seen forum (this forum and others) members with a PAR meter post results.

Since they are a sponsor, you can find some PAR data for Advanced LEDs here:

Advanced Led Datasheets

There is also a former sponsor that has a series of videos showing PAR measurements for their lights. It's probably against policy to post a link, so I won't.

So how many lumens would be needed at top of autoflower led lighting. 35000...

hey you there

well i came across your post, and thought i would reply.i cant pm u untill i have 50 posts, or win any gooodies.oh well. im gona put some pics of my ccaf.they are the two on the deck.i want cks seeds to respond to this issue on this forum. on this post.if they dont im gona start a new blog,thread, whatever its called. i tried following all your posts and stuff. first the ccaf`s u got are NOT autos at all. its the biggest messup by the biggest seeds co in the world.save your seeds if u have them.follow my posts i am -- ithinkican.so, youve been doing GREAT it sounds like.try posting some pics(if u mess up a few times .its ok) im going to flower my ccaf WHICH i have remamed as cc.1, outside in this winter spectrum of light.and its perfect 12/12 right now,anyways....im going to go respond to cks post i saw earlier and tell them something important. heres my advice for the seedling soil. use the same soil you use except what i do is put your amount of soil in towel and soak with water squeez it a few times till the runoff is fairly clear but not totally. fluff with fork dry slightly and lightly put into your container.the pics im putting up today are why i use the cages and today i lst them.and a cuple of my house.so im still practicing with pics ,i cant get them to post with the captions.so stay in touch.i might make some posts to get 50, u-2, ? so we can p.m. Happy growing.cya

Here bud whats up

Hey where abouts are you growing plants outside in winter? lol nice pictures Im trying to figure out how to get pictures to my journal ive created any idea how to get pics from my phone to here? lol

hey.what i do with the pics is from phone- hook to computersave in a folder-open forum page-go to gallery-goto download pics.if trying to just use phone,i havnt checked yet,i saw their thread on how to-too much info so didnt really read it.i will again.i would try save those pics in a folder on phone.open a new window.they have to download to 420 site first.i go to member photos and load mine one by one anyhooo.. what you think of the ccaf. read cks comments on thier site.its on youtube and on this forum. i live in eastern colorado. mild winters. any temps over 40 degrees i put them outside.the roots are warm enough to carry it threw the day. the light cycle is 12-12 now, so grow em inside, transition them for outside,cold/windy days i put in southern exposure window,i put mine in a dark room for the ldark cycle.it was record breaking weather here all week.in the 70`s.the winter sunrises and sunsets are so red/orange the light is so intense for buddin.i put sun screen around my deck yesterday, i mite put pic.black pots work better.cold wind is harder on them then hot wind.except for the indica dominant.they like cold breeze higher humidity. my CCAF(non-ccaf)(candy cane point 1)(CC.1).

Damn my candy cane looks nothing like such

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That is my next pots instead of plastic

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Purple kush is do good

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I'll get more pics later fir you of my set up lights cone on at 7 pm eastern time

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Canada

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