If you’re looking for a strong growing autumn variety of leek with long white stems that resist becoming ‘bulby’ then Leek ‘Mercurian F1’ is ideal for you. An upright, non-drooping leaf habit allows for good air circulation which minimises the risk of mould or infection.Sow indoors 4-5 seeds in 5cm (2in) pots or used vending cups, or very thinly in a seed tray of good quality seed compost. Cover with 6mm (¼in) of vermiculite or compost, maintaining a temperature of 15-20°C (59-68°F) until germination. Outside, sow thinly, 1cm (½in) deep in drills 30cm (12in) apart in soil which has been raked to a fine tilth.Carefully lift when plants are large enough to handle and transplant from May to July to 23-25cm (9-10in) apart in the row and 45cm (18in) between rows, using a trowel or dibber, and water in. Keep watered during dry weather. Earth up the stems during the growing season to increase the length of the blanched stem.