Eiffel, a British bred variety, is one of the best. It has distinctive stiff upright leaves and being slow to bulb will give you a smooth white stem. You can even sow under cover in October for the earliest crop in the following spring.
Price for 100 seeds
SOW: from March onwards in the open, no more than 1cm deep and sparingly to minimise thinning. By sowing every 3-4 weeks you can have a succession of salad onions.
GROW: you will only need to grow with protection or undercover for October sowings which can give you the earliest spring onions in the following year.
EAT: pull as needed. We often freeze spring onions after we cut them into strips to add to oriental dishes.