Last year was the warmest March on record: this year it has so far been the coldest. Spring ain’t what it used to be. None the less, it’s reliably time to harvest the ‘spring onions’.
I don’t mean the things you buy in the shops as spring onions (or scallions) since I don’t grow them. Let’s face it, onions are a pain to grow from seed. You need lots of added soil fertility and fanatical weeding of things that look regrettably similar to grass seedlings. Then, just as they are starting to look after themselves, you dig them up and eat them. By this time it’s usually August, which isn’t spring, not even here in Aberdeen.
tree onion
Fortunately there are two perennial vegetable species which produce excellent spring onions even when it’s still snowing and with very little fuss for the rest of the year: tree onion (Allium cepa proliferum) and welsh onion (Allium fistulosum).
Tree onion is the same species as the ordinary onion. A lot of allium species can produce either flowers or tiny bulbs called bulbils (or both) in their flower heads and tree onion is a kind of onion that goes for all bulbils. These often sprout when they’re still on the plant, giving it a tree-like appearance. The stem then usually falls over, giving the plant another of its many names – walking onion – as the bulbils put down roots and the plant ‘walks’ around the garden. It also reproduces by bulb division underground, like a shallot or a daffodil.
tree onion divided
This gives two ways to exploit tree onions for spring onions. First you can dig up the parent plant when it resprouts in the spring, divide out some of the bulbs and replant the rest. The other way is to gather the bulbils when they are produced later in the year and plant them out into a bed where they will grow on into very well shaped spring onions. It’s kind of like having a free supply of onion sets for spring onions and yet another name for this plant is ‘topset onion’ (You can also let them grow on into bulb onions, but they tend not to be very big.). You can plant some in the autumn for spring growth as they are extremely hardy but they will also keep well if you store them in a cool, dry place, so you can make successional sowings later on in the year too.
Welsh onion is a different species from regular onion but it’s very similar to tree onion. Instead of bulbils it produces a rather fleshy flower head which can also be used as a flavouring or left to produce seed (picking the flowers stops the plants producing seed and diverts their energy back into making bulbs). Like tree onions they divide underground and can be lifted and divided as spring onions in March and April.
welsh onion divided
Both species can also be harvested by picking leaves in the summer. I find that welsh onion makes bigger and more regular-sized spring onions by division and tree onion is better for leaves, partly because you can use the bulbils to produce a really dense patch. So the best use is probably welsh onions for division in the spring and tree onion for leaves and sets for growing on. If you allow welsh onions to flower you will be very popular with the bees.
Real spring onions can be used in all the same ways that you would use the seed-grown ones. My favourite is spring onion sambar: you fry a large handful of whole spring onions until they are soft, then add tamarind, coconut and spices to make a sauce and simmer for a few minutes. It’s a great way to forget the sleet driving at the window.
Hi Alan, I’ve been subscribed to your blog for some time now, but having found the time to read it from the beginning, I just wanted to tell you how enjoyable and informative I’ve found it. I am not in the position to have any kind of ‘proper’ forest garden, living in a rented house with a small garden, but, nontheless, I still grow lots of perennial vegetables, many of which you have blogged about here.
I look forward to more interesting posts. Here’s hoping we have a proper summer this year! Happy growing.
Joy
Hi Joy. Thanks very much. I so agree about the summer – I’m hoping that if a glorious March was followed by a non-summer last year then this wintry March will be followed by a memorably good one!
Growing these for the first time this year! Excited…
Have you ever grown perennial leeks (Allium Ampeloprasum)? They multiply by making little bulbs at their root like welsh onions, and they rarely make seed. The only cultivar I have ever found is “Oepri perizweib,” but I am told there is an Egyptian and Arabic cultivar as well.
Yes, I grow them too, although I have no idea what cultivar they may be. I originally got the seed for them from Future Foods and they have maintained themselves vegetatively ever since. The strain I grow has a mixed head of flowers and bulbils, so it does produce some seed which should be very useful for breeding them. I still have some bulbils from last year’s crop if you would like to swap varieties.
I would love to swap bulbils, but I’m in the US. Thanks for offering though.
Actually, I am waiting to receive the bulbils for “Oepri Perizweib” from the place I found them.
They said their leeks have only bloomed once in the seven years. But if I get seed, I would be happy to try and send you some.
Last year I let some ordinary leeks get to the flowering stage-they weren’t very successful as leeks, but the flowers were truly magnificent and I picked them for display-like large allium heads, some of them in a pale lavendery sort of colour, others a sort of silvery grey. When pulled out of the ground, to my surprise they were attached to a largeish garlic like bulb. My question is, can the bulb be eaten? I have saved 3 of them and planted in a pot to see if they’ll flower again
Cultivated leeks are derived from the species Allium ampeloprasum. They don’t usually form bulbs but other cultivars of the species, such as elephant garlic and Babington’s leek, do, so I suspect that the ancestral species also did. Perhaps a few of your cultivated leeks have reverted to old habits or perhaps they have crossed with one of the other cultivars. In the other cultivars the bulb is certainly edible, with a mild garlicky flavour. If you grow them on you might well find that they make multiple bulbs – perhaps you have discovered the next big perennial vegetable!