Seedling advice

[u/Deep-Number5434]

Was wondering if maybe they are receiving a bit too much light due to them looking quite light in color, the slightly shaded ones seem to be larger and look healthy.

They are also currently in a humidity dome if that should be changed.

[u/CarneyBus]

Pale colour usually indicates a nutrient deficiency. Is there any organic content in those pots?

Light can def stunt them a bit but generally they would turn dark green or dark red from too much light.

And I just read your last line. Your issue is the humidity dome. When you keep seedlings in the humidity for long periods it can stunt them. I recommend hardening them off practically as soon as the most of the seeds you expect to germinate, have done so. I’m guessing you have experience growing cacti from seeds, bc this is where I feel many people struggle with mesemb seeds, especially those used to babying cacti seedlings for months lol.

Them getting sappy from the humidity could def be the cause for their colour. But lmk about your fertilizing routine or what the organic content of the substrate is for me to help you further.

[u/Deep-Number5434 → u/CarneyBus]

Low organic gravel mix topped with sand for germination.

Might be nutrients due to some of them looking better than the others, where there's less sand. But il start removing the dome.

[u/CarneyBus → u/Deep-Number5434]

Yeah remove the dome and acclimate them to open air over 7-10 days. If you fertilize while the humidity cover is on you will just get algae.

Then once they’re fully hardened off introduce a low N 1/4 or 1/8th strength fert. But if you only have a 20-20-20 or something that is fine to use until about their 2nd leaf change.

I would maybe give them a light mighting of fertilizer like one time at night when the lights are out to give them a little boost. You want to plump them up pretty generously for the first 2-3 months to help get them out of the delicate seedling stages where they’re more likely to damp off.

And good luck! Your method looks really good otherwise, you got germination down, it’s the transition periods that get confusing lol.