Basics first--what type of light are you using? Some, especially the basil, look a little leggy. Also, are you intending permanent indoor culture, or will they go out when ready?

Basil--if the pot is 6" or less, then you definitely have too many for long term. Right now while they're growing it really isn't a problem, so you can let them go a little longer before thinning by cutting. But, if you want to try and root separate them, now is the time. I do 2 stems in a 12" pot and personally wouldn't go with anything smaller--it can get 2-3' tall and bushy when properly tended.

Lemon balm will just work itself out, but you could thin the marjoram by half if you'd like. Rosemary I've not grown from seed personally, but it's really a small shrub, so you will eventually go down to one. But you can probably leave them for now and see which ends up the strongest--I'd hate to thin and then lose the one to rootrot or whatever.

Thanks for the quick reply! No I haven't been using a light. I probably should have since here in Helsinki, Finland there isn't a lot of natural light this time of the year. But the days are getting longer. In a month the sun will be setting at 10:30pm and in the middle of summer almost at midnight. It's still a bit too cold but once the weather warms up, I'll put them on the balcony.

Ok good to know. That pot is only about 3" but it was only meant to be a temporary solution. Once I have more time I'll buy some bigger clay pots. 12" pots are huge though, I don't know if I have space for pots that size. I have 8 different kinds of herbs coming along and my windowsill could get a bit crowded. Do you have any space-saving suggestions? Oh and so I can thing the basil just by cutting? No need to get out the root? Can I also thin the marjoram the same way?

I'm not using any fertilizer. Is that something I should definitely start using?

Thanks again for the help! Things have been going so well and I'd hate for something to wrong. :( Needless to say, I'm a little stressed out haha

I disagree. You shouldn't repot until they get their first set of leaves.
When you repot you can use Miracle Gro liquid half strength. You can thin your cuttings by cutting the weakest ones out. I won't repot any of them into a 12" pot. Use a 3" or 4" pot until they get bigger. Even then that's a big jump.

Hi Johnny,

Wow--Finland! Very neat. What type of temps do you have once you start putting them out to go with all the light?

Hmmm...space saving. The thing is, many of the herbs you're growing can get very large, so you do need larger pots at that point. The cute pics of little windowsill herbs you see all over are usually forced, unhealthy plants that won't last much longer than the time it takes to stage the pic. My rosemary is also in a 12", but it's much larger. You can start smaller there--you don't want to go much bigger than the rootball because that just traps extra moisture and invites rootrot. My marjoram is in a 6" pot, and I just keep it trimmed. Lemon balm I don't do in a pot, but you could probably get away with a 6-8" and keep it trimmed. When happy, it wants to spread and take over the world.

Which brings us back to the basil. If you don't mind losing the extra seedlings, yes you can thin by just cutting the extras. Throw them in a salad or on pasta--right now they're micro greens and yummy. My husband loves the thinnings I cut from mine at this time of year. Otherwise, they do have their first true leaves, so it is also possible to carefully root separate them. I would decide how many you want to keep (and have bigger pots for) later when they can go out, and put them individually or in pairs in the 3" pots for now. My basil seedlings are in 2 1/2" waiting for warm enough weather for planting. If you have any sort of light you can supplement them with, it would be very helpful--you can see how much stockier mine are under fluorescent lights--they're also probably much older, sown March 12. A fan will also be good to strengthen the stems.

Fertilizer--I use a half strength liquid fish/seafood (no more than 3-2-2) on my seedlings at the time they get their first true leaves, then about every 2weeks for the seedlings. Once my potted herbs are grown (after at least 6 months in the pot), I fertilize them with the full strength fish/sea every 4-6 weeks during growing season, and once or twice overwinter inside. With transplants, the potting mix usually has enough nutrients for the first 6 months, as herbs are not heavy feeders. Thus, I don't fert my pots until they've been growing long enough to deplete the mix.

Also--with my comments on fertilizer. I also make sure the potting mixes I use don't contain fertilizer, or only nutrients in small amounts from something like vermicompost mixed in. If your potting mix has fert added, then you won't need to supplement unless they've been long potted.