[Eblana]

My daughter brought me home a 'present' of a pot of Mint and a pot of Basil from the supermarket so that I could grow some for her (she obviously didn't see the Basil seedlings in the greenhouse ).

The mint I have put in a pot - I don't grow mint because I don't want it taking over!

There are about 12 leggy plants in the basil pot - can these be potted on and should I pinch them out the tips to make them grow sturdier?

[Trillium]

If I have to buy started basil, I always separate them because as you've found, they do go leggy. As for pinching tops, wait until they have a few sets of leaves before doing so. Otherwise they can be finicky little primadonnas.

[Jonajo]

I must confess i do buy the odd pot of basil as well as sowing from seed. I use shed loads of it throughout the year. Its the only herb i do that for, but I still have 2 supermarket basils on a window sill that is going well over a year later. But yes, separate out for sure.

[angelavdavis]

You can propagate basil by putting cuttings in water - it will grow roots at a leaf axle.  Just remove the leaves first before placing in water and change water often.