Bad seeds? 5 seedlings dead within weeks

Hi growers

I started growing weed more than 10 years ago and had some very succesful grows with big plants and big yield.
This year and last year tho I've had tremendous problems and I can't figure out what is causing it. I hope you can help.

Plants are outdoor (Denmark) when the sun is out and the temperature is more than 10C. Kept indoor during night as the nights are still around 3-6C.
Soil is a normal medium from the local DYI store (not heavy) mixed with leca balls.
I'm not furtilizing at this early stage and the water is filtered.

It all stars out fine:


And then within 2 weeks it turns ugly.





In general the seedlings do strech a lot as the sun is not very intense in Denmark. I try to manage to give them 12 hrs a day at least. This should not kill them tho.
The round leaves quickly turn yellow. The seedling usually manages two more sets of leaves and then they turn yellow, curl together, start hanging etc.
I've tried wattering more. And I've tried letting them dry out a lot. Nothing seems to help.
The roots are very short. In two weeks only 1,5cm...I imagine this is the problem, but just can't make sense why the roots are not growing more.
We've had plenty of sun for danish standards at this time of the year.

I hope you have ideas as to what I'm doing wrong.

If the roots are not growing, than your medium sux. They might not be ready yet for direct sunlight as well…

Just to early and way to cold to go outside

I agree with Bukvičak, the soil is most likely the problem. And with Green Machine too, temps should be above 20c
Can you link the soil? Is it fresh? And does the shop keep the soil inside or outside?

They look like they have received nutrients either from soil or manually at a way to early stage

@Bukvičák:

Bukvičák said:

If the roots are not growing, than your medium sux. They might not be ready yet for direct sunlight as well…

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Not ready for direct sunlight? Didn't know that was a thing. I guess with normal outdoor grows, you'll have full sunlight exposure form day 1?

Hampovitch said:

@Bukvičák:

Not ready for direct sunlight? Didn't know that was a thing. I guess with normal outdoor grows, you'll have full sunlight exposure form day 1?

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Thats the difference. Search : hardening plants off

Astral22 said:

I agree with Bukvičak, the soil is most likely the problem. And with Green Machine too, temps should be above 20c
Can you link the soil? Is it fresh? And does the shop keep the soil inside or outside?

Click to expand...

In regards to the temperature outside it's often 13-17C in the garden they are in and they are in direct hot sunlight. However, the wind is cold and that might also be what stresses the plants? Perhaps it's better to have them only in the window, until it's warmer even though it would mean less sunlight.

I bought the soil very recently. Also I have two different soils now, quite similar but just to try another brand.
Perhaps the soil is too rich with nutriants and "burns" the plant?

bam0813 said:

Thats the difference. Search : hardening plants off

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That makes sense as is definitely something I havn't taken into consideration. I'm moving them in and out with sometimes 8-10C temperature difference I guess. And cold wind.

Ya indoors to out they need some transitional time to adjust

I think hardening you have to do when you have seedlings indoors and then you put them outdoors. Am i right or no ?

bam0813 said:

Thats the difference. Search : hardening plants off

Click to expand...

you don't need to harden plants that started outside. nothing would ever grow anywhere if that was true

0potato0 said:

you don't need to harden plants that started outside. nothing would ever grow anywhere if that was true

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Exactly how the fuck are they growing at Himalayan for example? Or back in the days without grow rooms

0potato0 said:

you don't need to harden plants that started outside. nothing would ever grow anywhere if that was true

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Exactly but he didn’t start them outside

Re read the thread

Bobkatar said:

Exactly how the fuck are they growing at Himalayan for example? Or back in the days without grow rooms

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How did they grow before paper towels

bam0813 said:

Exactly but he didn’t start them outside

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No that's true. They are stading inside until the seedling comes out. As soon as it's out it's been outdoor during the days tho. So in general more outdoors than indoors.

Hampovitch said:

No that's true. They are stading inside until the seedling comes out. As soon as it's out it's been outdoor during the days tho. So in general more outdoors than indoors.

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Its the change. I’m honestly not even saying thats your problem. Could be part of it. I was simply backing up the fact it should be done to plants started indoors as mentioned by someone else. Popping a seed in warm soil, and giving it a nice place to sleep at night is not the same as started outside imo however that is almost the hardening process

Hampovitch said:

In regards to the temperature outside it's often 13-17C in the garden they are in and they are in direct hot sunlight. However, the wind is cold and that might also be what stresses the plants? Perhaps it's better to have them only in the window, until it's warmer even though it would mean less sunlight.

I bought the soil very recently. Also I have two different soils now, quite similar but just to try another brand.
Perhaps the soil is too rich with nutriants and "burns" the plant?

Click to expand...

Way too cold

Billy the Mountain said:

Way too cold

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Thanks appreciate that insight! I'm actually growing 'royale dane' which is supposed to be able to handle the weather, but I'll try with the two I have left to keep them indoor until mid may and see if that helps.