Interesting read thank you, I struggle every year to work out what I need to buy. I always buy singly as I don’t want 2kg of one variety & where I buy from they just weigh the total amount in my basket at the scales which is great.
It does vary on how you grow them though, I plant my rows closer together as I grow in narrow no dig beds, so in my 5ft beds I plant 4 or 5 earlies & 3 main crop across the width & early rows are about 18-20” apart & main crop 24-30” apart. With doing no dig I just nestle them into the mulch, down to soil level & ‘earth’ up with more mulch.