Light height above the canopy.

Hey everyone I got a question for you great folks. When I first started growing everything I read said to keep the light about 1.5-2 feet above the canopy of your plants to prevent stretching and to keep your plants nice and compact and it will help with the density of the buds and most of all prevent stretching. However lately I have been seeing many many grows where people have the light hung up way higher than 2 feet from the canopy. Anytime I tried that my plants stretched to reach the light. But I got them about 2 feet from the canopy but I’m having issues with temps reaching 32 Celsius. I had issues with my last grow where one plant stretched so much it basically outgrew my tent. Some tips or information will be greatly appreciated.

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Depends on what light really. What light you running ?

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And 32c breaks down to just under 90 f. So that’s at top end of where I like to see things. Where is that temp from? Whole room, above lights or right at canopy ?

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The 32c is right at the top of the canopy but the plant is only about 6 inches high at this point. If I put the light any higher the plant will stretch too much. Using a mars hydro 3000 and growing autos.

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Plants stretching is a given, some strains (Sativas) stretch more than others…check out this plant, it so close 2", to my HPS light but it didn’t burn the plant because my lights are on a light mover…buds came out nice and compact and of course sugar coated as a mofo



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My mars 2000 is about 8” from the canopy right now.

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Honestly each light is different, and each grow is different depending on environmental factors and such some can be mounted 10-12 inches with ease. Some can’t get closer than 2ft especially at 100% my suggestion would be start at the max and work your way down slowly. Checking leaf temps and watching the plants and how they react closely. Plants will tell you when they are happy and when they are not. But honestly are so much more resilient than most think. A very Hardy plant that grows pretty much worldwide (with exceptions) truly a magical plant gifted to us so we can heal ourselves, rather than hurt ourselves with handfuls of pharmaceuticals.

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I never had an issue with stretching in the 20 years I been growing unless the plant was far away from the light. I usually keep it 1.5-2 feet above the canopy and ALWAYS got shorter fat plants compared to everyone else who kept their light high. I had a buddy who got a 6 foot tent, his light is about 5 feet off the floor. His plants stretched right to the light and his buds were airy and poor quality.

I’m sure the ones with it way up have stronger light… depends on space vs light distance vs light intensity I’d think

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Ultimately it has to do with spectrum… red makes em stretch… blue keeps em short… etc. …

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I have my two 600 watt hps light hung at six feet in a 4x8x7. The plants stay squat till I flip then I get some regular stretch… I grow mainly indica dom too, might help. If I lower those lights I get burn…

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I do agree with you about the spectrum effects stretch

I also believe it’s genetics as well
Some plants just get big

Tent hight and light size makes a big difference in environment

My concern mainly in the tent once the plant stretches is the distribution of the light along the sides , some lights that do not cover the whole ceiling dimensions of the tent( like mine ) l need the hight to distribute the light to the further most area

If I can keep a 24 to 28 in distance between the plant and the light I get max coverage

No need for supplemental lighting

Just rambling
I’m going to do 2 grow one with and one without supplemental lighting just to see what happens
To the environment , heat rh ect and yield and stress issues

Should be fun

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That’s going to be a good comparison man!!! Cold hard facts are the best

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my lights are ~34inches from the tip of the cloth pot. 48w of red+far red stay on along.

the shelves the octos are resting on are 110cm/43in from the lights.

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My plants do great with them being placed up there.

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My last grow I had a Dark Devil auto about a week or two behind the other 3. Every time I moved the light up because the other 3 needed the space the dark devil stretched bad. It was about 4 feet high from the top of the bucket. I might get a quarter from it.

I firmly believe it’s the breeding/genetics and how powerful your lighting is…

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LOL I have seen pictures like that and been like WTF? They are supposed to be good genetics. Barney’s Farm, Sweet Seeds and couple other those type of breeders.

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Second picture, the plant to the right back was the dark devil. A week maybe two weeks later it was like it is in the first picture. That is way too much stretching to say it’s normal. The Dark devil auto is from sweet seeds.

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Whatever works for your specific plants.
Following the manufacturer guidelines of whatever light you’re using is a good start.
32 Celsius is a fine temperature.
If your plant looks healthy then who cares about numbers.
Don’t overthink it, and don’t be afraid of experimenting.

Some plants stretch, others don’t.
A lot of it is genetic.

And I have grown Dark Devil, it didn’t stretch like that at all.

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