I would probably take a small chunk of soil with a couple of plants at a time and plant directly into your prepared garden bed. Water in.

If you want to harvest over a longer period, pinch out terminal leaves taking no more than 1/3 of the living plant material (this means leaves!) at a time. You'll have to wait until you can do what I said and have enough to harvest plus enough for the plant to survive.

FataMorgana

great! thanks... that should be fairly easy as they have grown in groups of two or three it seems

My basil looks exactly like that (but it's under glass) and I have already started harvesting it. You can snip a few sprouts to thin them out and you can use them in your cooking right now.

Hi there,
I just started a bunch of basil a couple of months for the first time too. If you google 'pricking out basil' - you'll find a couple of youtube videos that are helpful.