Seedlings: what am I doing wrong?

[Bevelman]

This keeps happening to me. I soak some seeds for 24 hours. This time cannatonic fem. I put them in paper towel until they germinate and the root is about 3/4" long. I then carefully transfer to peat pellets. I put them in a jiffy pot with a clear dome. I am using led lights about 4 ft above the seedlings. I have a temp of 75° and humidity of 95%. They grow about an inch, and the first set of leaves grow out. sometimes the second starts, but inevitably they die. They just stop growing after a week and no roots appear out of the peat. Anyone got any ideas of what I should be doing differently.
TIA Greg

 

[skirk]

Lose the dome and get some air circulation @Bevelman. Without pics, my guess is they're damping off. Also. I know the dry weight of my Jiffy is 11 grams and saturated is 53 grams. I add water when it gets to 20 grams and keep 10 grams below saturated. This keeps me out of problems. Good luck

 

[CO Finest]

They are not a clone they do not need to go into a dome. You are drowning them to death with way to much water and moisture. After towel go straight into pot damp soil before transplanting. You can mist spray water on soil after transplant to settle soil but do not water until lifting up pot and it feels almost empty. Over water rots roots slows growth and then stops all growth then dead. Plant with root brings water inside from root plants without root aka clone brings water in by leafs and steams. If sounds like your way over doing it which is normal with a lot of newer growers. I also recommend practicing with cheap tomato seeds when you get time. Same thing with them get root go into light damp soil or whatever your using. Peat pellets work but not needed at all. Solo cups or any plastic cups can be reused.

 

[Nunyabiz]

Yep, dampening off from way too high humidity and probably way to wet overall.

Soak in room temp filtered water with a tiny amount of aloe vera mixed in for about 24 hours then transfer to paper towel wet with the aloe vera water.
Put that in a spot that stays about 80 degrees such as top of fridge or a router.

Soon as you see the seed crack with just the tiniest little white tip showing go ahead and plant into whatever pot , either a solo cup for a week or so and then to final pot or if you water properly can just put right into final pot.

 

[Bevelman]

Thanks guys. It seems unanimous, too much water. I realized I should posted pics, so I went and took some. Just for a laugh, I included some pics of a 2" and 3" autoflower budding.

 

[Sancheh]

I'm not sure size of led but perhaps it could be dropped down from 4ft

 

[Grandma Weedstein]

Thanks guys. It seems unanimous, too much water. I realized I should posted pics, so I went and took some. Just for a laugh, I included some pics of a 2" and 3" autoflower budding.

Definitely overwatered. Are the autoflowers the result of this technique?

 

[Bevelman]

I am using a 1000 watt led. The pictures are 2 weeks after going into peat. The autoflowers are the same but different. The middle of the stem turned brown in the peat, so just for shits and grins I transplanted them with the brown part below the soil..

 

[Grandma Weedstein]

I am using a 1000 watt led. The pictures are 2 weeks after going into peat. The autoflowers are the same but different. The middle of the stem turned brown in the peat, so just for shits and grins I transplanted them with the brown part below the soil..

Maybe they rooted from the part of the stem that wasn’t rotting. I like the above idea about practicing germination with tomato seeds.

It’s really easy to overwater — I did it with some plants earlier this year despite trying not to. (Had them in shitty soil and in a weird position where the pots sat in runoff, didn’t realize until too late.)

Once you get seedlings past that crucial early stage, though, they tend to be pretty hard, especially in veg. I’ve seen a couple basically bounce back from near-death. Tougher to get them to rejuvenate in flower, as they stop vigorously producing new foliage.

 

[NuttyProfessor]

strange that i do my seedlings a a blubber dome and it works , the peat must be killing them off , are the blocks ph ed? i ph at 5.6

P1080587.JPG

• NuttyProfessor
• Jul 25, 2020

P1080574.JPG

• NuttyProfessor
• Jul 25, 2020

 

[NuttyProfessor]

also use some CFL or t5s they enjoy them better than leds , i bet the light will also make a difference, and dont add bark to the tops some barks lower the ph to less than 5 , Little seedlings hate strong leds too soon ,

this is my ones that where in the dome germinated didnt harm them at all that humidity : its your lights and ph i bet

 

[multiVortex]

I use a dome when finishing seedlings. But I do it very carefully.

I think the bigger issue is the peat pellets. They get way too wet, way too easy.


Here’s what I do, and if a seed is going to pop, it will.


1) GENTLY scarify the seed with sandpaper

2) soak in filtered water 24-48 hours. If no tails by 48hrs, move to step 3 anyway.

3) take a rapid rooter, flat end down. Poke hole in top with tweezers. Dip in water, squeeze out. Repeat that a few times, and on the final one don’t squeeze too hard. It should be moist, but not soaked. Use tweezers to move seed from shot glass to rooter. If the hole doesn’t self seal, pinch off a spec from the bottom corner and use that over the hole. (Tiny piece!)

4) place rooter onto wicking mat in dome.

// seedling dome is sitting on a temp controlled heat mat set to 78F. There is a wicking mat that lays across a small tray inside, and the end of the mat touches the bottom. The dome as 4 air vents that start off closed. This sits under 2 LED “shop” strip lights, about 18” above the top of the dome.


5) I use a very light dose of nutes, like 20% of week 1 veg, plus 2ml/gal of cal mag. I fill the tray about an inch, put the temp probe into another rooter (wire comes through one of the vents), and put the dome on.

6) check rooters morning, afternoon, and evening until a sprout comes up.

7) once it does, wait for the day after next, and open two air vents. (So for example, if it comes up Thursday night, then Saturday morning/early afternoon is when you would do this step.)

8) after 2 more days, take the lid off.




This works, but doesn’t damp them off if done correctly. The real trick is getting the rooter at or just below the right moisture level. With a wicking mat, it help to go a hair to the dry side, as it will balance itself out.

What does this do with the dome?

For the first wait, it gives the seedling time to come up and get its act together. Keeping the lid on helps the seedling leaves (cotyledons) while the very first roots get going.

When the vents open, it drops the humidity a good bit, closer to normal.

At this time it also provides an adjustment period to the light.


Once the dome is off, you've done all you can and ma nature is running the show.


Too wet: damp off and die.

Too dry: still die.


Find: The Goldilocks Zone.

 

[Grandma Weedstein]

I use a dome when finishing seedlings. But I do it very carefully.

I think the bigger issue is the peat pellets. They get way too wet, way too easy.


Here’s what I do, and if a seed is going to pop, it will.


1) GENTLY scarify the seed with sandpaper

2) soak in filtered water 24-48 hours. If no tails by 48hrs, move to step 3 anyway.

3) take a rapid rooter, flat end down. Poke hole in top with tweezers. Dip in water, squeeze out. Repeat that a few times, and on the final one don’t squeeze too hard. It should be moist, but not soaked. Use tweezers to move seed from shot glass to rooter. If the hole doesn’t self seal, pinch off a spec from the bottom corner and use that over the hole. (Tiny piece!)

4) place rooter onto wicking mat in dome.

// seedling dome is sitting on a temp controlled heat mat set to 78F. There is a wicking mat that lays across a small tray inside, and the end of the mat touches the bottom. The dome as 4 air vents that start off closed. This sits under 2 LED “shop” strip lights, about 18” above the top of the dome.


5) I use a very light dose of nutes, like 20% of week 1 veg, plus 2ml/gal of cal mag. I fill the tray about an inch, put the temp probe into another rooter (wire comes through one of the vents), and put the dome on.

6) check rooters morning, afternoon, and evening until a sprout comes up.

7) once it does, wait for the day after next, and open two air vents. (So for example, if it comes up Thursday night, then Saturday morning/early afternoon is when you would do this step.)

8) after 2 more days, take the lid off.




This works, but doesn’t damp them off if done correctly. The real trick is getting the rooter at or just below the right moisture level. With a wicking mat, it help to go a hair to the dry side, as it will balance itself out.

What does this do with the dome?

For the first wait, it gives the seedling time to come up and get its act together. Keeping the lid on helps the seedling leaves (cotyledons) while the very first roots get going.

When the vents open, it drops the humidity a good bit, closer to normal.

At this time it also provides an adjustment period to the light.


Once the dome is off, you've done all you can and ma nature is running the show.


Too wet: damp off and die.

Too dry: still die.


Find: The Goldilocks Zone.

If that works for you, that’s fine, but I have a simpler method:

Soak seeds in water overnight, plant roughly 1/4 inch deep in moist soil. Mist soil until seedling pops, then stop watering until soil begins drying out.