Can anyone tell me what colours to mix to get terra cotta colour for a flower pot?

Try brown and slowly add orange.You can tone it down a bit with a drop of black or if you like the color then leave it!!

Thanks. I will give it a try.

I second Kiddiekakes method!

I've also used a Wilton color called Copper which gives a deep clay color. Actually one of the prettier colors I've made with a Wilton product!