Point one: they're not artichokes, and they're not from Jerusalem, says Mark Diacono.
Jerusalem artichokes were one of the first things I grew when I got the gardening bug and they’ve been present in my garden ever since. Everything about them makes me feel good (caveats apply; see a few paragraphs down). They are trouble-free and delicious, but — and I don’t say this lightly — I might grow them even if I didn’t find them delicious, such is their generosity throughout the year.
Firstly, let’s deal with their name: they are neither artichokes, nor from Jerusalem. They are sunflowers and the Italian for sunflower is girasole, which appears to have morphed into Jerusalem over the centuries. They are native to the river basins of the US, which perhaps explains why they thrived when I grew them close to the River Otter here in Devon. They love both full sun and a fertile, moist soil.
Their engine room comes in the form of knobbly tubers. Once the weather warms up, these tubers fire into life, producing tall, thick stems that often reach 6ft–10ft. If you grow them in a thick line as I do, they form something of a seasonal windbreak, providing shade and shelter for crops on the least exposed side.
In a sunny summer, the tall stems produce extraordinary flowers that, although smaller than familiar sunflowers, more than deserve their place in the same family. Increasingly, they are being used here in the UK as florists’ cut flowers (as they are commonly in Italy).
They’re not cheap, either. I cut the flowers for the house, which earns me much-needed good-husband points and diverts the plant’s energies from the flowers to the developing tubers and, in turn, to winter meals.
The flowers also bring hoverflies, bees and ladybirds into the garden that will act as pollinators and/or happily tackle a few seasonal pests such as aphids. When it comes to harvesting the tubers as autumn turns to winter, all of that enthusiastic growth can be added to the compost heap and contribute to the fertility of next year’s garden.
On top of all that, artichokes provide one of my favourite harvests of the year. Although you can find the tubers in a few shops, they are not commonly for sale: you’re better to grow them yourself. They have a distinctive earthy, sweet, almost mushroomy flavour that makes an excellent soup and perhaps my favourite risotto; they roast well and make superb crisps.
I know a few people are put off by their supposed invasiveness; in truth, they are like potatoes, any unharvested will grow and multiply the following year. Unlike potatoes, buy them once and you have them for as long as you want, if you leave some to grow the following year, without any risk of diseases building up as a result. Jerusalem artichokes also produce well in a large container, but water them regularly and feed occasionally for the best chance of both flowers and a hefty crop.
“They all taste the same, so go for one of the less knobbly kinds to make peeling them easier”
The caveat: some of the starch is in the form of inulin, which most of us can’t digest readily, and can cause some — as an old school pal used to put it — to play a merry tune on the bowel bugle. If you are affected, eating them with parsley seems to greatly reduce this — which is handy as they go together so well — and the more you eat them, the better your body deals with the inulin.
There aren’t that many varieties to choose from and, in my experience, they all taste the same, so go for one of the less knobbly kinds, such as Fuseau, to make peeling them (if you do) easier. Winter is the time to source them for planting in spring. I usually sink them 6in down and about 24in from their neighbour.
Once planted, there’s nothing to do (apart from cut late-summer flowers), until the frosts knock back the top growth. As with parsnips, the onset of cold can help convert those starches into sugars, increasing the sweetness and reducing any potential for ‘disturbance’.
The tubers don’t store well, but they are cold-hardy, so don’t pick them before you want to eat them. If the ground is frozen too hard to dig, simply wait until it thaws and they’ll be fine to harvest then. Any you leave will multiply the following year, giving you all its generous gifts for nothing.
Mark Diacono grows edibles, both usual and unusual, at Otter Farm in Devon — www.otterfarm.co.uk
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