Blimey ..did not know growing spuds was so complicated...plant em deep, all a foot apart and earth them up high staright away..works for me for all varities..this is a mixture of other peoples advice, teaching commercial horticulture with FE nd HE , being a horticutural therapist, reading , watching and learning from others ..plus my own experiences .

I didn't say I used it! I plant 4 rows every year in one of my 10' beds that are 25-28' long, how many per row depends on how many there are in the bag.
This year it is a 27' bed and so far one row is 10 Vales Emerald and 17 Rocket and the other is 10 Red Duke of York and 17 Rocket. The other two rows will probably go in this weekend, 22 Charlotte and 27 Red Duke of York.