Undoubtedly an heirloom, the name American Blue Flag can be traced back to the 1870s. Leeks travelled to America with European settlers, so this variety’s roots are quite possibly British! Some link it to the old variety ‘Broad London’, while others suggest ‘Scottish Flag’.
Whatever its exact ancestry, there’s no doubt this is an impressive variety. There’s that broad fan of blue-green leaves sitting above the famously large, thick shank, typically 20-25cm long and 5-8cm across, although occasionally much longer. The flavour is mild and oniony with a touch of sweetness, particularly after a spell of cold weather.
This variety is part of our naturally nurtured range, the seed comes from an organic source.
Sow: from March to the end of May for harvesting from October through to the following March. We sow our leeks in modules, 10mm deep, rather than a seed bed. Allow 8-12 weeks from sowing before planting out, harden off first.
Grow: plant out one leek per 15cm deep hole made with a dibber or stick. Water the leek into the hole and let the soil wash in around it, trying not to get soil between the leaves. It sounds fiddly but leeks are worth the trouble. If it is dry after planting water gently every day while they settle in, but otherwise just leave them to grow! Allow about 20 weeks after transplanting before you start harvesting, at this point the shanks will be about 2-3cm across. They’re winter hardy, so you can leave them for longer to thicken those shanks and harvest into the new year.
Enjoy: with all that mild, sweet leek to play with, these are brilliant sliced into soups and stews, softened slowly in butter or tucked under a cheese sauce and baked. And because they're happy standing through winter, you can simply lift one when you need it
💡 Did you know?
Leeks like firm soil, so bear that in mind when choosing where to plant them. They can follow crops such as lettuce, cabbage or peas. If you're planting after early potatoes, firm the freshly disturbed soil well before your leeks go in.
Save
