"Grow Your Own Tobacco" Law in the UK - FreeSmoking.co.uk
I think this site says that it's ok if your a "hobby grower", i.e no intention of distribution of your final product.

I may give it a bash if I move, I think that I would section off the part I was growing it in, and sort of make a box in the ground to grow it in soil (I dunno whats that called, lol), so I could change the soil rather than actually fucking up the ground.