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Slow seedling growth under LED

Iron Emmett

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Hey MP

I was just wondering if any of you folks who have grown their seedlings under led have experienced extremely slow growth?

Ive got 3 seedlings going that are 12 days from fully shedding their bean helms and standing upright, and they still have only their initial leaf set, ive never seen seedlings grow so slowly.

im running this light http://www.mars-hydro.com/reflector-led-grow-light-192-3w-77.html in a 3x2 tent, my ventilation is good, my temps are good, my water is ph'ed fine, the beans werent old or anything.

i previously had them in my little veg area under this light http://www.mars-hydro.com/reflector-led-grow-light-96-3w-75.html but i moved them to the big light when they werent growing just to see if they werent getting enough light, i had the light in the veg area at like 14 inchs

i cant figure out why they are growing so slowly, i currently have the light at about 18 inchs from top, is that too close? too far?

ill drop some pics here if anyone wants to see them, they look healthy they just arent growing.

First grow with LED kinda lost :)

Thanks all.
 

Rosebud

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Sorry Iron, i haven't started seeds under my LED's yet. I think Power Planter did and is having a slow start as well. I use my t5's then go to led. Wish I could help. Calling PJ!!!
 
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P Jammers

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Sorry Iron, i haven't started seeds under my LED's yet. I think Power Planter did and is having a slow start as well. I use my t5's then go to led. Wish I could help. Calling PJ!!!
You rang?

I'd blame everything other than the light TBH. I have seeds ready to flip in 21 days from crack normally and the plants are much tighter compared to other types of lighting.

That said I typically run hybrids that have lots of vigor and don't run too many pure breads now a days which are typically a lot slower at the start.

Let's see some pics and maybe we can make a determination.
 

Rosebud

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Man Pj, you are awesome...Do I have you on speed think?
 

powerplanter

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I thought mine were growing slow and moved my light closer and almost burnt them up. I can't help much cause this is only my second grow indoors.
 

Iron Emmett

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Thanks for stopping in guys, i appreciate your input.

PJ, what height do you run your lights usually for seedlings?

Heres some pics, they havent been fed just given PH'ed water with some mycorrhizal for root growth, but its 0-0-0.

Also, all 3 of them sprouted completely purple, the tops of the leaves are greener now but all the bots are still full purple, included that in the pics, never seen it before :)

They are in Rapid rooters, in Coco with perlite 50/50 ratio, and the strain is God Bud x Blue Cheese by Jordan of the Isles


View attachment rsz_sam_0248.jpg

View attachment rsz_sam_0244.jpg
 
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P Jammers

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You are basically starving the plants to death. Coco, perlite are both inert and add nothing to the plants at all.

Give them a lite feeding suggested for seedlings, and back the light off to 2 feet until you see them start to take off. Right now you are at the mercy of whatever you water contains, and for sure it is not rich in nitrogen. Just be real careful not to over-water at this stage as well as that will add to unhealthy roots which will certainly be death. I would also add a teaspoon of epsom salts per gallon, or a Calcium/Magnesium supplement at half the suggested rate. Another must for seeds going in to Coco...

Your lights should be good at 12" to 16" "IF" you are using them with veg lights only on. If you're running full spectrum 24" or so as there is just too much red that early in growth and leaves can burn.

Might also be a good idea to get a seed mat under the plants as LED's will not create any real surface temperature either which was going to be my first stab in the dark this time a year.
;)

In other words, it's not the lights my friend.

Best of luck and keep us posted!
 

Iron Emmett

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Thanks for the reply, now i understand that coco and perlite are both inert and have nothing in them, but from all my previous grow i saw fine growth with waiting to feed until i get some real leaf formation, never had seedlings do this before with the same medium. I didnt wanna feed em and hurt em since they were so small.

Perhaps the seeds are slow starters or early feeders and that is contributing, i didnt want to sound like i was condemning the lights, if thats the impression that was a mistake, i was curious if anyone had experienced the slow seedlings with the lights so it was my first reaction, thanks for the replies i appreciate your input once again, ill try a feeding and see what happens.
 
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P Jammers

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Thanks for the reply, now i understand that coco and perlite are both inert and have nothing in them, but from all my previous grow i saw fine growth with waiting to feed until i get some real leaf formation, never had seedlings do this before with the same medium. I didnt wanna feed em and hurt em since they were so small.

Perhaps the seeds are slow starters or early feeders and that is contributing, i didnt want to sound like i was condemning the lights, if thats the impression that was a mistake, i was curious if anyone had experienced the slow seedlings with the lights so it was my first reaction, thanks for the replies i appreciate your input once again, ill try a feeding and see what happens.
It could be as simple as the water you re using is not exactly the same as it was last time no matter of it is coming from the same spot or not. Could also be the coco. Do you charge it previous to use?

For sure you are magnesium deficient causing that purple, and nitrogen as well. If the food and or PH is off, you'll notice it ten fold LED vs T5/HID growing.
 

Iron Emmett

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I run distilled water, but i dunno what you mean by charge, i dont use any amendments or lime, i just do a good soak with ph'ed water until the run off is in good levels.

I will be extra vigilant i didnt realize that problems were so much for noticeable with LEDs
 
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I run distilled water, but i dunno what you mean by charge, i dont use any amendments or lime, i just do a good soak with ph'ed water until the run off is in good levels.

I will be extra vigilant i didnt realize that problems were so much for noticeable with LEDs
Charge = Pre soaking your medium for 24 hours with a Cal/Mag supplement at 10ML per gallon for 24 hours previous to use.

That alone will I bet solve your issues.
 

Iron Emmett

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Cool man, thanks for that tip, i usually just add Ca;/Mag when i feed, ill try this next time.
 

powerplanter

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Hey IE, did you figure out why the slow growth? Mine are really slow still. Could be the cooler weather like PJ said. I was just curious what you think... :)
 

ncmga

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Greetings
I just recently purchased a super grow led sk 450 @ $800 250 w led. This is experiment only to see differences in most conventional lighting. In my grows, I usually start with flouresents for 2 wks or so then for flower I then use 3200K MH lamps. I to this day have NEVER used an HPS lamp. Reason being that the medicinal quality of cannabis is much higher. I know the yield is low, but the quality is high. Even DJ Short claimed that UV MH lighting produces high oil(trihomes) glands that if done correctly produces Delta 9. Any how leds do seem slow compared to fluorescents or HID. I used to use OTT LITES super brites years ago and if they still made them I would without hesitation buy again as growth was astonishing. Stay the course and if u can get/use fulvic acid at 1 tsp(teaspoon) qt (quart) that causes fast upper green growth and if possible get/use kelp for astonishing early growth.

Atomic Dog
 

techrons78

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Well I started my grow with floors for 2 weeks or so...put a 300 with vegc switch and 360 flower..was growing slow. ..he told me to get rid of other light only use the veg switch at 3 feet..they started to grow much better..grew like. That. For 2weeks maybe 3 improved 100 percent..they so use Way less nutes and water...everytime I feed them they grow an inch it seems like in a day...but I love my leds....tech
 
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I used OTT lights years ago, too, but have never looked back. I would not go back to them for any amount of money. They were way overhyped and all the grows I saw anywhere, they underperformed HPS by miles.
 

ncmga

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Greetings

Ott Lights (lites) were a group of fluorescents that were used by Walt Disney animation from the 50s. They did a time lapse film of plant growth using these full spectrum lightning. Apparently, Mr Ott was able to get the spectrum in correct balance to propagate foilage and flowers. The lamps that I am speaking of is the electromagnetic radiation shielded lighting. Most all electron or e instruments give off pulses that can cause abnormal growth in plants. Ott found a way to diffuse the radiation so that plants could respond in their natural frequency. I wish they still made these lamps as they were very bright and had a balanced spectrum compared to other light sources. The original like I had was rated at 33,000hrs. The average brightness was above average to other fluorescents in its class. Average astonishing growth with average starting cost. Most beginners, novices, and professionals alike can effectively use this system for large or small gardens. KISS... Keep It Simple and Safe.

Peace
Atomic Dog
 
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Other may have good luck with them, but I simply did not. Way back when, our choices for lighting were very limited and I thought the OTT lights looked great....but they simply weren't (for me anyway). They produced pretty much like any other CFL.
 

DankHobbyist

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You rang?

I'd blame everything other than the light TBH. I have seeds ready to flip in 21 days from crack normally and the plants are much tighter compared to other types of lighting.

That said I typically run hybrids that have lots of vigor and don't run too many pure breads now a days which are typically a lot slower at the start.

Let's see some pics and maybe we can make a determination.
Out of curiosity why a purebreds slower to start? Is it indica or dative trait? Why does it work out this way? that post caught my attn. What do you look for when you go blind on a choice of seeds as far as finding something that starts quicker. Is this a trade off somewhere. Thanks PJ.
 

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