I keep them in the cube a couple weeks. Just until they have their first true leaves and I have a chance to get them in the garden. They go from here to their final pot.
I am very bad at lights and wattage etc. I use LEDs everywhere. My preferred method for seedling lights is a shop light. One of the tube jobs. As close as I can get them. I also like a humidity dome. I’ll frequently set my light on top of the dome. I start vegetable seeds on a rack with the tube LEDs. Weed seeds I start differently. I just put some in water, I’ll tag you in my grow log and you can check it out if you’re interested
They call this “stretching” or “leggy” and it’s not desirable, when they get really long and spindly it’s a sign your light is too far away.
I have a preference short seedlings, just a preference. I will transplant up to the cotyledon either way, but especially if they are leggy.
The Chernobyl im growing now tends to be leggy no matter what you do, but grows out of it.
If you have leggy ones you can always transplant it deeper and cover the stem, it will shoot roots, or only fill half of the solo cup and then fill with soil if needed …
Thanks, I see the leaves curled and maybe bleached , your lamp is at a correct distance but maybe too intense? I use the Phototone app to measure that intensity, this would be the correct range:
Yes @George, they were too intense but I already adjusted that. You can see that the following leaves are ok. Photone does not work on my smartphone. Thank you!