Brown Tips On 2 Day Old Seedlings...?

[Uckemfup]

My seedlings tips started turning brown within the first two days after coming up...I’ve since moved the light to a further distance, but it was already at 36 inches to begin with (6 cob 3000k light, running at 50w per cob) What is/was my problem? Different seedlings show different signs of stress. I planted in root riot cubes to pop seeds but placed these directly in uncharged 3 gal coco smart pots from the beginning. Too much light too soon? The new growth seems to be normal.

 

[crimsonecho]

If the new growth doesn’t show the symptoms and the only thing you changed is light distance then it is probably the lights. Did you feed them?

 

[Uckemfup]

Nope not yet, they’re on day 6 now, as in the pics. Should I feed them now or when? I was thinking 04/13 I’d feed them as that would be about the 12 day mark.

 

[Uckemfup]

This dude LOOKS like he needs food...but idk. He’s a little droopy and middle veins a bit reddish, but none of the others have this either??

 

[Uckemfup]

Without more info that's might be some big pots for the size of plants. Don't claim to know about cob lighting. But it could also be too much light. Imo everyone might need more info for help

What info would help?

 

[Uckemfup]

not yet, should I?

If the new growth doesn’t show the symptoms and the only thing you changed is light distance then it is probably the lights. Did you feed them?

 

[Uckemfup]

They look small and young. I would never be in a hurry to use nutes. Many plant have dyed from over nuking them. What are you growing in soil , co co ?

Coco, uncharged

 

[Uckemfup]

Maybe a little cal mag if in coco or to water

I’m using 32 base ppm well water, pHed to around 6.5. ...how much cal mag should I add? Thanks for ur help btw

 

[BudLMA]

It says 1ml per 1l but I would go a bit less to start. .5ml per 1l ph between 5.7-6.3 depending on grow medium

 

[crimsonecho]

not yet, should I?

I asked because the tips are yellowing which is sometimes a sign of nute burn and i wanted to make sure you are not burning them with too much nutes. No you shouldn’t feed just yet but from what i read coco lacks the required calcium so you may want to add calcium in your prefered method but they are still very small i would wait for the 3rd node at least.

 

[stonestacker]

What medium are you in? I don't know how long a seedling will survive without food, but you should always feed coco. Never straight water. For what it's worth. 3 gallon pot for a seedling is hard to pull off.

 

[crimsonecho]

I asked because the tips are yellowing which is sometimes a sign of nute burn and i wanted to make sure you are not burning them with too much nutes. No you shouldn’t feed just yet but from what i read coco lacks the required calcium so you may want to add calcium in your prefered method but they are still very small i would wait for the 3rd node at least.

What medium are you in? I don't know how long a seedling will survive without food, but you should always feed coco. Never straight water. For what it's worth. 3 gallon pot for a seedling is hard to pull off.

I agree with you and rescind my comment i don’t grow in coco, only in organic living soil so i based the no feed part of my comment on that experience. I think you sould do a light feed with a balanced fertilizer.

 

[Uckemfup]

What medium are you in? I don't know how long a seedling will survive without food, but you should always feed coco. Never straight water. For what it's worth. 3 gallon pot for a seedling is hard to pull off.

Yah it’s becoming super hard to pull off...coco won’t evaporate even though I’m only putting in small amounts of water, even though I have above average airflow ... Idk if it’s overwater or underwater ...I haven’t watered these for 2 days and last time only a cup in a circle around it. It’s still damp under the surface, it’s 70 coco/30 perlite. Should I down pot or is it too late...

 

[BudLMA]

Coco needs calmag from what ive read from the start. I just started growing in coco and have used calmag at 1/2 strength at an ec of 0.5. The seedlings are looking healthy so far and its day 8. I have a cfl 125w 5inches away. People do replant so it should be ok?

 

[stonestacker]

I would feed 1/4 - 1/2 strength veg food. If you didn't flush or pre charge the coco. I would flush real good with veg food with cal mag. Then play the try not to let it dry out too much while not over feeding and drowning the plants. Waiting for the pot to fill with roots so you can daily feed to runoff.
Nothing to it lol. You will get it.

 

[Uckemfup]

I would feed 1/4 - 1/2 strength veg food. If you didn't flush or pre charge the coco. I would flush real good with veg food with cal mag. Then play the try not to let it dry out too much while not over feeding and drowning the plants. Waiting for the pot to fill with roots so you can daily feed to runoff.
Nothing to it lol. You will get it.

I flushed but no precharge

 

[Uckemfup]

I would feed 1/4 - 1/2 strength veg food. If you didn't flush or pre charge the coco. I would flush real good with veg food with cal mag. Then play the try not to let it dry out too much while not over feeding and drowning the plants. Waiting for the pot to fill with roots so you can daily feed to runoff.
Nothing to it lol. You will get it.

So I used 1/4 (a little less actually) strength nutes and 1/4 strength cal mag, watered moderately but I still didn’t soak the entire 3gal pot. My temps have been 77 day, 66-68 night w a RH of 50. 10 plants in 3 gal smart pots, 6 cobs @50w each are at 43” away, so I’m hoping temp or light distance isn’t the reason...but what is it? The symptoms have showed on the new growth now.

 

[stonestacker]

To me that plant is saying feed me. Your coco still looks too dry to me but I can't pick up the pot. Coco should never be allowed to dry out. Should always feel like a wrung out sponge. Damp but not dripping. New growth is light green if it doesn't darken in the next day or 2 you need more N. Or just bring total ppms up a little. I would soak that pot at least once a week until you can water to run off on a daily basis. With daily small watering to keep your plants health with fresh feed and o2 being pulled down to the roots. You get problems when you let your coco dry out it traps salts in your coco. Then when it gets watered it will release said salts and mess up your ppm ratio.

 

[thosedamnkids]

I asked because the tips are yellowing which is sometimes a sign of nute burn and i wanted to make sure you are not burning them with too much nutes. No you shouldn’t feed just yet but from what i read coco lacks the required calcium so you may want to add calcium in your prefered method but they are still very small i would wait for the 3rd node at least.

I agree, I would wait. Looks like nute burn to me. If it was the lights it would be more than just the tips.

 

[Uckemfup]

I agree, I would wait. Looks like nute burn to me. If it was the lights it would be more than just the tips.

It could be nute burn...IF I had used any nutes at that point, but I hadnt. lol.
They looked like that in rapid rooters before the roots ever emerged into uncharged coco (my fault) . I’ve since soaked the coco w seedling strength nutes + calmag on the advice of @stonestacker and they seem to be doing better/growing a bit faster. This is them now...they still look pale imo? Top pic was the worst looking one @ first.