I would put it in the ground or if you have a greenhouse sink the pot in the ground there & when the first flowers form feed it with tomato feed. :o))
Oh! Water the plant well before, also take out any side shots that come from were the leaves are as I think I can see some. But if its a bush one leave them on, best to find out from your neighbour which one it is first? :O))

If you are going to leave it in a pot that one looks a bit on the small side. 11-12 " is better. Also give it plenty of water.

Thanks Ladyessex1. Apparently they are cherry tomatoes.
Don't have a greenhouse; I don't really understand - do I leave them in their pots and put the pots in the ground? Take off ALL side shoots?

Leave the side shoots on, plant in pots about 12 inches tall and 12 inches across at the top, I use Organic soil myself or cheap buckets and drill some holes in the bottom, add some crocks or stones for drainage first.
To make it easier go tho this web site......

http://www.organicgardening.com/learn-and-grow/cherry-tomatoes-easiest-plant-youll-ever-grow

Good Luck Jackie :O)

In 12" pota they won't need to go in the ground but be very regular in watering. You might find it helpful to stand the pots on a plastic pot saucer. Cherry tomatoes are bush ones.

Thanks everybody. I feel I might get a crop now!