They look ok. For now I would just leave them as is. The root systems are brand new and you wouldn't want o disturb it. Maybe next year, pot them up individually.

As a pine they are meant to be outside and are going to need a cold treatment. I would start thinking of how to accomplish that come winter. Having less than optimal lighting will make them leggy and thin. Try to get them as much bright light as possible, if outdoors is not an option.

Did the kit mention what type of pine? You have quite a while before you'll start training them as bonsai. Have patience.

I will echo what Kev said and also say they need to be outside all year round. They need lots of Sunlight. It is probably a Japanese Black pine. In winter they need to be protected and there are various ways of doing that depending on cold it gets. But they need to be out there in the cold though. They also need very well drained soil so that they are not soggy.

It will be a while before they can be trained as bonsai. You should read up on various articles on the plant. There are plenty.

Thanks for everyone your replies!

It is japanese black pine.

To my eyes, they look to grow quite fast. I attach fresh photos to show how they progress. The time difference between these two (new) photos and the one in my first post is 4 days. To your experience how the growth rate looks like please?

I am also wondering if I let them (all five) in that pot until next year, lets say January 2010, will their roots have become too widespread and tangled up to separate them. Can this pot support all 5 please?

If you also have any links to recommend for japanese black pine bonsais it will be highly appreciated. I am an absolute beginner here.

Many thanks!

Start with this article: https://www.evergreengardenworks.com/pines.htm

They will initially grow fast and then slow down when there is no space left in the soil to grow more roots. It is actually easier to transplant young seedlings into separate pots since they are quite vigorous at this stage. But you can leave till next year and transplant around April. You can do it earlier if you are in a warmer zone. In my zone 6b end of April will be a good time.

Th epot cannot really support all five. It may be OK till next year.

Can u help me are these

Ok?

don't think I separated them enough because I thought this is how the kit called for it said they would not all germinate....

Put each plant in its own plastic pot with drainage holes and then slowly get them acclimated to the outside. What are you using for potting mix?

tj