New Grower: Help! Seedlings falling over

I searched the forums but I couldn’t find anything that would fit my situation.

I germinated my OG Kush Autos in rock wool. they started popping 5 days ago. I had them in a propagator with/ Dome and heating pad. I immediately lower a 2’ - 2 bulb T5 light close to the dome without touching it. The early sprouts stretched to the top of the dome by day 3. I had to remove the dome, still keeping the light as close as possible. I turned a fan on low to try and strengthen the stems.

The early ones still kept stretching. I assumed that they must be reaching for the light. Yesterday I removed the T5 and lowered a 600-watt full spectrum led to slow the stretch. I had to give the Rockwool a spray or two because they were drying faster than normal. ( I assume)

Today 2 seedlings feel over. I propped them up with toothpicks. I noticed that the main vein of the leaves and the second pair of true leaves seemed to be a little yellow. I raised the light about 6", but I don’t know what the hell I’m doing!!!

I have a 1020 tray with 7" dome coming. What else can I do or look for?

Your time and help are much appreciated!


You nailed it IMO by replacing light source. Can’t fix the stretch now but when they get transplanted you can bury the stem as deeply as you wish. Best to keep domed so good call on the taller dome. You can (and did) prop them up with a popsicle stick or whatever. With adequate light (FYI) the sprouts end up like 1/2" high. 10 days or so before any nutes at all and then go easy: 200 ppm at 6.0 PH will do fine. A little Superthrive (B vitamin) is good too.

What media are you planning on using? Soil? Coco? Hydro?



Thanks MyFriend,

I’m just feeling around in the dark so it is great that I am able to come here and receive help from kind people as yourself.

I am going to be growing ebb and flow in Hydroton and 2-Gallon buckets. I’m a little concerned with the yellowing. Did I bring the larger light too close?

Thanks again!


No; they’re just showing signs of N deficiency. Once you have root poking out the bottom of the rock wool you can start nutrient regime.

You are taking on an ambitious first grow…personally I would recommend a soil grow just to see the lifecycle of the cannabis plant. Once you have a grow under your belt it gets far less tense lol.


Lol… I just thought that was the way it was done.


I believe I figured out the yellowing and the tips turning down. I believe I was overwatering. I was trying to compensate for not having a dome and having the fans on. I picked up the inner tray and I could tell the Rockwool was about saturated.

Thanks again for your help


Well…go big or go home right… LoL damned if you do damned if ya don’t…your gonna go places…I’m set to watch this one…good luck man we are around when you need us!!



I guess I’ll have to rent a warehouse for my next grow, hehe. I’m glad you found this thread… I’m gonna need all the help I can get!

Thanks, LoCo


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Cool :tiger2:, I’m glad I did too but I’m still learning too. Will be for the rest of my life. Great great forum man, you’ll never find a better bunch of ppl… :+1:


No water since yesterday and the yellow is 95% gone. I’m going to drain the H2O2 mix tonight. I should have the reservoir mixed and the seedlings in the buckets tomorrow.

Should I stay with 500ppm since they are still seedlings or bump it up some?

I still don’t understand why the 1st ones to pop stretched so much. The two that popped late didn’t stretch.

Definitely keep it light - 1/4 strength … did you move the light at all? It’s a double t5 - u can get pretty close with that!! Good job :+1:

I’m guessing 1/4 strength would be about 200 PPM? I had the double T5 as close as I could get without raising the temp too high (about 2" - 3") when the early ones stretched. I turned on one 600 watt led and raised it about 14"… the stretch slowed. I am wrestling with keeping them watered without a dome. I hope all that will be over tomorrow when I plug them in.

Thanks LoCo

I finally plugged the girls into the system. I’ll give a brief(?) description of the system.

6, 2-gallon ebb & flow buckets, (Active~Aqua)

2 - 25-gallon reservoirs w/air-pump extra water pump for circulation

6" carbon filter with 450CFM in-line blower w/2-speed control

6 - 600-watt Full spectrum (not burple) LED grow=lights

2 Century timers. plugged into 2 dedicated 15amp lines
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
RO water GH Armor SI, Flora series @ 204 PPM PH - 5.45

Seedling pics coming


Bumped the ph to 6


The girls seem to have taken to their new pot… well… all except one. It was one of the last to pop. It has received the exact same treatment as the others. It is even sharing a pot with the other late popper. I may have to cull it but I’ll wait for now.
Rather than try to describe the issue… here is a pic

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She’s looking worse. Any thoughts? The 8 others are looking healthy and most are larger with 2 nodes

I made an attempt to top 2 of them but I think I FIMed them. My plants are still very close to the hydroton!

Whatcha think… and be brutally honest. I hoped this grow would go smooth, but I knew I’d stumble some feeling around in the dark !

I started LST the two I FIMed and one more that was tall enough


It looks a little early to be cutting the plants in anyway! Usually no hacking away until they have about 3 - 5 nodes. That’s when topping of fim can begin!! If Im seeing what I think I’m seeing???


That does look a bit young, how old? Autos do need trained early but that might be a little too early. Most wait for 3 or 4 nodes

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