When to transplant seedlings?

After planting the Acer Palmatum seed I collected in the fall, I'm flush with new seedlings.

Does anyone have any advice as to when to transplant the seedlings from the seed tray and into larger pots. They have their first set of real leaves, but the cotelydns are still attached.

Thoughts and suggestions?

thanks,

Cordon

most of the information I can find says wait until the second set of leaves emerge. So i guess that's what I'll wait for. Another couple weeks or so. Why is the waiting the hardest part?

Cordon

How and where are you growing these? Inside? Outside? Are you providing heat?

For now they are inside. They get good morning sun and then indirect light the rest of the day. On warm days this month I'll acclimatize them to the outdoors. Once they are potted up and the weather permits they will be moved outside.