On Mon, 27 Apr 2009 09:59:34 +0100, TheOldFellow wrote:

One bit of advice I've had says use
tomato fertilizer, but this I would have thought would promote flowers,
not tubers. So, any advice please (on any aspect of this)?

R.

The tubers are, biologically speaking, modified shoots (not roots as one
might suppose). IANAE but I would think general fertiliser to promote
growth of plants such as Miracle Grow would be appropriate?