Our gardening expert on the divisive tubers
Jerusalem artichokes tend to divide people. To some they are the devil’s work, whereas others can’t get enough, particularly at this time of year, when the tubers have been mellowed and sweetened by frost. I fall firmly into the second category. I love their nutty flavour and will eat them every which way, from sliced as thinly as possible in salads with, say, a little blue cheese and watercress, gently sautéed with leeks, baked in a gratin, or folded into a silken soup. And then, before I am beaten by what seems an inexhaustible supply, I make them into chutney for summer ploughman’s lunches.
If you fall into the former category this is probably because you once ate them and no one warned you about the after-effect. Jerusalem artichokes store their starch in the form of inulin; this makes them very good for diabetics and others who need a low-starch diet; it also means that, initially, there’s often a lot of gas and bloating.
Inulin is a prebiotic and is very good for your gut health, but your gut often doesn’t have quite the right flora at the beginning of the artichoke season. You need to build up stamina; start by eating a little jerusalem artichoke, thinly sliced and raw – going straight in with a gratin will be disastrous – and eat plenty of live yoghurt or other probiotics. Another option to take the wind out of them is to lacto-ferment them, which means fermenting in 2-3% brine (20-30g of salt in 1 litre of water). I like them with ginger, garlic, chilli and turmeric.
Jerusalem artichokes are perennial – and prolific. In order that they don’t take over your world, you need to eat them into submission, which should be happening now. By late March they will start to sprout again.
For this reason, it is also the best time to establish them. They need to be planted 10-15cm deep with 30cm between tubers and 1.5m between rows. Jerusalem artichokes are closely related to sunflowers and grow over 3m tall with small, jolly yellow flowers that appear in October. You need to grow them somewhere they won’t shade out other crops.
They are sometimes cited as good windbreaks, but the truth is they will topple in strong winds. You can earth them up in late spring, but a better trick is to cut them back to around 1.5m tall in midsummer. This way they shouldn’t need staking. Fuseau is a French variety with smooth skins for easy peeling. Dwarf Sunray grows to only 150cm high, so it’s good for smaller or windy spots. You can also use supermarket-bought tubers if you can’t find a named supply.