Help with seedlings. First grow.

[cachexic]

I'm 12 days into my grow. I'm growing autoflowers (Samsquanch OG by Mephisto Genetics) in coco/perlite. I have six of them, all currently in pint-sized fabric nursery bags.

Couple of the seedlings have brown spots. Overall growth seems to be on the slow side. Color seems off.

The only thing I know I could do better is the relative humidity, which is currently only 40-45%. I'm waiting on a humidity dome that's big enough to hold all the plants, which is being delivered in a couple days. Other than that, I can't make heads or tails of any of this. Temperature about 78 degrees F. Using GH nutrient line. I'm measuring inflow PH / EC + runoff EC. Numbers are fine. I would be grateful for input as I'm starting to not know what to do.

 

[Failmore]

I grew plants from seed in the winter with no dome. My rh is 22%. So not needed but it helps.

What light? How far is it?

Ec for feed should be 0.5 or so.

Do you have a fan blowing directly on them? You should?

Heat will be trapped under the lip of that bag and burn the plant. So you need wind blowing directly on the plant to change out the air in that bag.

 

[cachexic]

I grew plants from seed in the winter with no dome. My rh is 22%. So not needed but it helps.

What light? How far is it?

Ec for feed should be 0.5 or so.

Do you have a fan blowing directly on them? You should?

Heat will be trapped under the lip of that bag and burn the plant. So you need wind blowing directly on the plant to change out the air in that bag.

1. Light is Mars Hydro SP3000 (300w true power draw). I have it about 12 inches from the seedlings at 40% power per manufacturer recommendations to give me about 300 umol.

2. Nutrient blend started at 400 EC for seedlings and have been gradually increasing per a guide I'm following. The oldest seedlings are up to 750 EC, with the two youngest taking 500 EC at their last fertigation.

3. I do not have a fan blowing directly on the plants for fear of drying them out with the low humidity. I've never read that before, about the heat being trapped and burning the plant, hmm... I will put a fan on them when I get home.

 

[MickFoster]

Extremely small for 12 days old.
Ditch the dome.........domes are for clones, not seedlings.
Did you pre-charge your coco?
What is your feeding schedule?
10 days old in coco for a comparison.

 

[cachexic]

Extremely small for 12 days old.
Ditch the dome.........domes are for clones, not seedlings.
Did you pre-charge your coco?
What is your feeding schedule?
10 days old in coco for a comparison.
View attachment 4862672

1. I did wash/buffer the coco. I washed all of it through a strainer, then let it soak in a 150% strength Calmag solution for 8 hours twice.

2. Once or twice a day, depending on how dry the medium was at the end of the night. The youngest two have only gotten once a day though so far.

3. Yours look so much better. I should note that I mean 12 days from placing seed in wet paper towel, not 12 days from sprout. And a couple of them germinated slower, so the youngest ones are like....7 days from sprout.

 

[Failmore]

It's coco so the medium will be moist at all times. Cant dry them out with a fan. Just saying from my experience. I burned up some seedling by having them lower than the lip without a fan.

Just a gentle breeze blowing down on the top to stir the air

 

[cachexic]

It's coco so the medium will be moist at all times. Cant dry them out with a fan. Just saying from my experience. I burned up some seedling by having them lower than the lip without a fan.

Just a gentle breeze blowing down on the top to stir the air

I will try. Thank you for weighing in, I certainly appreciate it.

 

[Johiem]

I'd be more concerned with mold developing due to lack of circulation around the stalk

 

[Lowkeygardener]

Looks like your young leaves are shying away from your light. This early on you could get away with around 26 Watts of CFL per seedling. 40% of your 300 watts at 12” away seems like overkill to me. Raise your light significantly until you start seeing some stretch then adjust accordingly until you find that sweet spot.

 

[Lowkeygardener]

Also, it’s better to have at least 50-70% humidity for these young seedlings. It will help your root growth significantly. I always run 24/0 light schedule in the seedling stage with good airflow and some indirect wind blowing on them to stimulate stem growth/strength. The better your root structure and stem structure, the more vigorously they will grow.

 

[cachexic]

Looks like your young leaves are shying away from your light. This early on you could get away with around 26 Watts of CFL per seedling. 40% of your 300 watts at 12” away seems like overkill to me. Raise your light significantly until you start seeing some stretch then adjust accordingly until you find that sweet spot.

Thanks for your input. Good point. I'm going to experiment with this.

 

[xtsho]

You don't need a dome. You're overfeeding them. You don't need to water seedlings every day if the coco is still soaking wet even if it is coco.

 

[Relaxed]

any nuts on those sure will kill em. Whats the crap soil u have them in probably killing em?

 

[cachexic]

You don't need a dome. You're overfeeding them. You don't need to water seedlings every day if the coco is still soaking wet even if it is coco.

The coco is not soaking wet when I water it -- not even moist at the top. Just cool to the touch. I apply 60-80ML or so to get a small amount of runoff.

 

[cachexic]

any nuts on those sure will kill em. Whats the crap soil u have them in probably killing em?

Not soil -- coco coir mixed with perlite. Coco was washed/strained/double-buffered with 150% strength Calmag solution prior to being potted up.

EDIT: Should note that before the seedlings were placed in the coco, I flushed water through it to get EC of the coco below 100 per the guide I'm following.

 

[Relaxed]

Not soil -- coco coir mixed with perlite. Coco was washed/strained/double-buffered with 150% strength Calmag solution prior to being potted up.

EDIT: Should note that before the seedlings were placed in the coco, I flushed water through it to get EC of the coco below 100 per the guide I'm following.

I am a soil guy so good luck. When I see the new guy and the failing plants tell me "the guide I am following:" needs fixed cause the guide isn;t being followed lol.

 

[cachexic]

I am a soil guy so good luck. When I see the new guy and the failing plants tell me "the guide I am following:" needs fixed cause the guide isn;t being followed lol.

Uh huh... Thanks for your help.

 

[MickFoster]

EDIT: Should note that before the seedlings were placed in the coco, I flushed water through it to get EC of the coco below 100 per the guide I'm following.

Never run plain water through coco..........you messed up the cations and washed out the calcium/magnesium solution that you soaked your coco in for 8 hours.

 

[cachexic]

Never run plain water through coco..........you messed up the cations and washed out the calcium/magnesium solution that you soaked your coco in for 8 hours.

But isn't the EC way too high for the seedlings otherwise? I think it was like 1000 before flushing.

EDIT: attached image of the instructions I followed, for reference, from cocoforcannabis.com

 

[JimmyJackCorn]

I am not a coco guy, but I agree with the folks saying it's a light and air issue.

I had good luck with seedlings in soil with my TSW2000 (MarsHydro 300W) at 24" and about 25%. And circulating air in those cups will replenish CO2, discourage pests and problems, and strenghten the stem.

If I were you I'd raise the light and turn it down, then cut that top lip off with some scissors so a fan can push a bit of air across them.