The moon was full last night so I’m thinking about harvest. You can see other posts in this series by following my ‘harvest’ tag. This month, let’s admire the leek.
At this time of year in Britain the leek (Allium ampeloprasum porrum) is in its glory. Leeks are seen in our shops in late summer and in autumn, but British Leeks, voice of the British Leek Growers Association (BLGA), says that this crop is at its best from November to April.
People have been eating leeks for thousands of years and we’re still eating them. Here’s what In Depth Info says about leek history. Here’s some of BLGA’s praise of this great vegetable.
‘A favourite food of the Romans, leeks are lauded in the Bible (Book of Numbers), have been eaten by saints (St. David), worn by the Welsh into battle and are said to possess mystical qualities.
• So if like the Emperor Nero you want to improve your singing voice – eat leeks!
• If you want to see your future husband – sleep with a leek under your pillow!
• If you want to repel invading Saxons – wear a leek in your helmet!
‘Alternatively, if you’re looking for a delicious, nutritious and seasonal food to see you through the winter months. Something that can be roasted, baked or braised and has a sweet taste and a smooth texture – then the British Leek is for you!’
In modern times, most leek growing in Britain happens in East Anglia, the English Midlands and the Scottish Borders. Richard Crane and Rod Vaughan of Reading University tell us about the regional importance of horticulture in England and Wales, sadly without Scotland and Northern Ireland. You can scroll down to page 16 for their map. Here are contact details for some major leek growers in Cambridgeshire, Lincolnshire, Nottinghamshire, Staffordshire and Berwickshire.
This blog entry honours Wales in particular, because the leek is the Welsh national symbol. Here’s a film about The Leek – Emblem of Wales. Apparently some Welsh people proudly wear leeks on St David’s Day, which is the First of March (this Friday) but to tell the truth, I’ve lived in Wales and I’ve never seen anybody wearing a leek. Plenty of people eating leeks, but no leeks pinned to helmets.
In any case the Centre for Alternative Land Use (CALU), based in Gwynedd, North Wales, provides a crop production guide for leeks. Andrew Forgrave at the Daily Post tells us about leek growing in Flintshire, North Wales.
Amateur gardeners grow leeks too. This crop does occupy the land for up to ten months, and it does need some attention (planting out, watering, earthing up) but it’s almost disease-free. Gardeners can take advice from the Royal Horticultural Society, the BBC, Garden Action and Allotment Growers. Later, they can take advice about harvesting and storing leeks from Garden Fresco.
I’ve grown leeks and other crops of the onion family (Alliaceae) many times in gardens and on allotments. But like many allotments, my last plot suffered the ravages of white rot (Sclerotium cepivorum). This disease, also called Allium white rot (AWR) is truly devastating to these crops. When it’s in your soil it stays there and there’s no cure.
This feels personal to me because my first science job, when I left school in the mid 1980s, was in the white rot research group which is now part of the Warwick Crop Centre. That was the summer when I learned how to do labwork and fieldwork.
Here’s a summary of the Warwick group’s continuing research. I don’t claim to have kept up with their work, but here’s an idea of what they’re doing. They’re working on AWR and also on another fungal disease of Allium spp., Fusarium basal rot (FBR).
• ‘Epidemiology and effect of environmental conditions on S. cepivorum and its interaction with microbial antagonists.’ What does the white rot fungus like and dislike? How could growers make it so uncomfortable that it’d disappear?
• ‘Biological control of AWR and FBR using Trichoderma spp. and composts.’ Could leek growers and onion growers introduce a friendly fungus to attack the white rot and basal rot fungi? Could they introduce composted onion waste as a decoy – tricking the white rot fungus into germinating, when there are no actual onions for it to grow on? If so, maybe it would starve.
• ‘Screening of onion diversity sets for resistance to FBR’ Could onions, leeks and other crops like them be selectively bred to resist disease?
One of these years, these scientists will find out how to get rid of these diseases. Here’s one of their reports about progress with the biological control strategy and the decoy strategy.
The leek looks like a possible target for genetic modification (GM), doesn’t it? You might choose to follow my ‘genetic modification’ tag for more posts on this.
• Weed control. One day there could be Roundup Ready leeks.
• Pathogen resistance. This means fungi such as S. cepivorum, and viruses too.
• Pest resistance. One day there could be leeks expressing the Bacillus thuringiensis (Bt) toxin and other insecticides.
• Quality for storing and eating.
• Development of the plant as it grows.
Field trials are underway in New Zealand but so far, no GM leek or onion has been approved for commercial use.
Meanwhile if you like leeks, now’s a good time to cook them. They’re versatile, delicious and nutritious.
[Edit] Here’s what my fellow blogger Katherine A Preston at The Botanist in the Kitchen says about a look at leeks.
[Edit] Here’s what my fellow blogger Ma Larkin at Tales from Riverside says about harvesting and storing leeks.