How slowly should I raise the PAR on my auto seedlings?

Hello, I’ve been told to start my seedlings at approx. 200 PAR, and gradually raise it to 600 through veg and then go up to 1000 for flower. My question is how quickly or slowly should I go from 200 to 600 with young autos? I have 4 plants just starting week 2 today. They’ve been at about 225 since a few days after they sprouted, and they look like they’re doing pretty well. I don’t want to go up too much and hurt them, but I don’t want to waste any time either because they’re autos. What do you think, can I go up to about 325 to 350? And how long should I wait to go up a bit again?
Thank you very much!

My personal opinion is I would have them at 600 now. 400-600 is optimal for early veg. 200-400 for seedlings,clones, and mothers. Anything over 1000 will burn carbs.

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Thank you very much @VTGROW. I’ll bump it up when they come back on this afternoon.

@VTGROW I have been thinking about picking up the Hydrofarm Quantum PAR meter. As a hobbyist / personal grower can’t quite see springing for an Apogee. May I ask you and Cap_Ron what you use? Familiar w/ Hydrofarm PAR meter :-1: :+1: or your recommendation on a different meter. I have a LUX meter and of course need to convert to PAR which is iffy because I have a full spectrum LED. I use waveform Lighting’s online converter. I think their Red Blue spectrum is pretty close to my light.

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I’ve never really measured till recently but got this one just to mess with. To be honest, I just go by how my girls respond, and this meter came outta the box twice. Once at my place and once at my buddies.

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Thanks - similar to what I have. I lux meter. I got one out of curiosity and because I am adding another light I wanted to know how much of a difference it makes.

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That’s exactly what I got from my local grow store @beardless. Of course I have no way of knowing exactly how accurate it is, but it seems very consistent and reliable. I have a Nextlight Mega in my closet, an ES300 in one tent, and a Grow 300 in another tent. The Quantum meter shows pretty much exactly what the manufacturers specs say on all three fixtures, so I’d say it’s a great deal for the price. Like you said, the Apogee ones will set you back the price of another fixture, lol.

Thanks for the info. Are you using it to dial in DLI or simply curious. I am adding a four strip Photo Boost fixture to supplement my current light and would like to see where the combination comes in at. Converting LUX to PAR will really get screwed up so I am talking myself into needing a PAR meter. I think it is working! :sunglasses:

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I hadn’t heard of DLI yet when I bought the meter. I figured since I went in debt so deep to get my fixtures I at least wanted the satisfaction of seeing the readings. I came across an article about DLI on maximum yield dot com fairly recently, and I’m definitely going to read more before I start my next big grow. A lot of what I read made sense. My plants always look terrible in the hours before lights out. I used to always think they were under or over watered, but it doesn’t matter. It seems as if they’ve had enough and are ready for a break before the 18 hours is up.

I’m just looking into it myself. Sounds logical - but in the end you need the horses to pull the cart

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You know guys I’ve never tracked it. Lol. Dbrn gave me a % and height and I just stick with that but now…see damn it …you’ve sparked my curiosity…guess what I’m buying thanks to you guys. My wife says :face_with_symbols_over_mouth: thanks alot :joy::joy::joy:
@dbrn32 what are your thoughts on par range and should I know that? I see it after the lights a few years old to see how your performance may have dropped.

Save your money, just grow the weed.


What’s that? Sounds interesting? Lol
I started growing to save money now I just find ways to spend it on growing.

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You don’t need a par meter


You DO need a PAR meter. otherwise you are guessing