First time planting seeds in coco. Fucked 'em all up. Any ideas?

Title says it all. I've always popped 'em in soil without a problem but this time I did canna coco flushed with water then charged with 400ppm fertilizer. All seeds but 1 popped out of 8 but after 2 days growth stopped. Cotyledons curled down and got brittle.

I figure it's 1 of 2 things that could have caused it. My light was too strong or the coco was charged too strong. I'm leaning hard towards the light being the cause, but I need some coco experts to chime in. I've never planted seedlings under this particular light and I think it was too intense for the babies. I think they just shriveled up. Never felt crispy clotyledons before.

As an experiment I pulled the dead seedlings and replaced them with tomato and lettuce seeds in 6 or so containers. Same coco. I've moved the plants under a light I always use for seedlings that is much less intense. If the lettuce and tomato seeds sprout and grow without a problem and keep growing I'll narrow it down to the light. If not then I'm kinda stumped. Maybe I should have started in rapid rooters or does it look like the light fried 'em? Sorry for the pic quality.

too wet

What light/distance were they under? Also, did you have them covered with a dome? Also, temp?

Rurumo said:

What light/distance were they under? Also, did you have them covered with a dome? Also, temp?

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Dome covered, 5' distance from the light, and 77F temp.
Damping off is a possibility. I've always planted in light warrior and it doesn't really hold much moisture.

Rurumo said:

What light/distance were they under? Also, did you have them covered with a dome? Also, temp?

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Would you suggest no dome and wringing the water out of the coco a bit more?

Plants sprout under the sun
I doubt your light was that bright
But 400ppm feed and a dome sound like a lack of research
Domes are for clones

I think you need to pull the dome. Keep the coco damp until she sets decent roots then bump it up. The water droplets on the leaves with intense light could have upset them too.

jonnynobody said:

Would you suggest no dome and wringing the water out of the coco a bit more?

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Don’t manipulate the coco
You will break tiny root hairs and shock your plants
Just let it air out

Yeah, I would bet it was too damp due to the dome. The top of the coco will dry out quickly, so just keep an eye on it and when it dries out too much, just give it a spray from a spray bottle, just until they sprout, then give them a wet dry cycle until the roots fill out.

Those styrofoam cups would work well for insulating a real solo cup, but I wouldn’t put media directly in them!

jonnynobody said:

Title says it all. I've always popped 'em in soil without a problem but this time I did canna coco flushed with water then charged with 400ppm fertilizer.

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I start them in Promix in a small pot. Then into coco using autopots.

No need to start them in coco if you've already got it working another way.

Herb & Suds said:

Plants sprout under the sun
I doubt your light was that bright
But 400ppm feed and a dome sound like a lack of research
Domes are for clones

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Do you recommend charging the coco at all before planting the seeds or would you wait until 10 or so days in to feed 150-200ppm?
I've planted every seed I've ever grown in soil inside a humidity dome without a problem. Last 30 I planted 28 got above the dirt in 3 or so days. Broad mites ate 'em alive, but that's another conversation. I basically did the same thing I do with soil. Epic failure though. I agree with you on the lighting. I don't believe the light was the cause. I root clones in a clone tote. I've never used a dome for clones, but that may be a soil thing.

Rurumo said:

Yeah, I would bet it was too damp due to the dome. The top of the coco will dry out quickly, so just keep an eye on it and when it dries out too much, just give it a spray from a spray bottle, just until they sprout, then give them a wet dry cycle until the roots fill out.

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Much appreciated. I'll take the dome off of the tray tonight and just hit 'em with a light spray of water on top of the coco if it looks like it's drying too much. I've got some veggie seeds planted in the same containers with the same coco I used for the canna-seeds I just killed. No dome this time. If I see some healthy tomato and lettuce sprouts growing nicely I'll come back to this thread and post a few pics.

dirtydoper1991 said:

I think you need to pull the dome. Keep the coco damp until she sets decent roots then bump it up. The water droplets on the leaves with intense light could have upset them too.

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Much appreciated! Dome gone baby gone.

resinhead said:

Those styrofoam cups would work well for insulating a real solo cup, but I wouldn’t put media directly in them!

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Why?

NotTheRobot said:

I start them in Promix in a small pot. Then into coco using autopots.

No need to start them in coco if you've already got it working another way.

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Why do you prefer starting in the promix versus planting straight into the coco?

jonnynobody said:

Why do you prefer starting in the promix versus planting straight into the coco?

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Starting in promix works for me.

I'll add that I start the seeds under an 18 watt light with no nutes and they grow every single time.

jonnynobody said:

Why?

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because cannabis is a remediating plant that absorbs petrochemicals. That and the roots would likely try to stick to the unsmooth surface.
It’s just personal preference though. It was the domes that did your seedlings in though. I’d recommend less nutes too. Ease them into life by keeping them wanting more.

Like others said, looks like damping off.

Next time, after you wet the coco, try and push some water out before dropping the seed in. I fill my cup with a loose coco/perlite mix, pour water in to really soak the crap out of it, then push down to compact it a bit and in the process push moisture out the bottom drain holes. Drop seed on top and kind of cover/bury it.

I recommend soaking your seeds overnight before planting, seems to sprout a bit quicker than just going straight into the medium. Getting them to pop and start growing quickly seems important in terms of getting ahead of any pathogens/molds/etc that pop up while sprouting. Try and keep them at a constant warm temp rather than having warm cold periods.

I use styrofoam if that's all I have. They don't stay in my cups long enough to absorb anything. About 10 days and they are moved up to liter pots.

cindysid said:

I use styrofoam if that's all I have. They don't stay in my cups long enough to absorb anything. About 10 days and they are moved up to liter pots.

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it’s just not the best choice. He wants ideas, so I thought I’d share that… invest in a package of solo cups. They can be re used for years.

resinhead said:

it’s just not the best choice. He wants ideas, so I thought I’d share that… invest in a package of solo cups. They can be re used for years.

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Every time I use one of those styrofoam cups I ask myself why I haven't bought a nice set of seedling containers. It's about time I think.