A tall, perennial, sunflower like plant that grows in full sun, in almost any type of soil to produce knobbly tubers that contain inulin and can be eaten raw or cooked.
The Jerusalem artichoke (also called sunchokes) – Helianthus tuberosus – is in the Asteraceae family like globe artichokes, though they are more like Chinese artichokes in the Lamiaceae family. Like Chinese artichokes, you harvest the tubers and propagate via tubers. Jerusalem artichokes however make tall, impressive plants like globe artichokes. Like the Chinese artichokes, posted last week, this is my first year growing them, so I have limited experience. I do love them though, so I thought it would be worth sharing and I can update as I find more about them.
How to grow
These came in a gourmet roots pack with Chinese artichokes as little plants. They were put in the ground in May, but like Chinese artichoke these can be grown from tubers, and like Chinese artichokes if any tubers are left in the ground then plants will come back next year and are therefore perennial. Because the tubers are larger than the Chinese artichokes you are less likely to leave some behind. I will keep a tuber spare in some potting compost in the shed over winter in case I’m too thorough with harvesting. Each tuber is capable of producing more than one shoot.
Jerusalem artichokes will do fine in just about any soil, except waterlogged as this will rot the roots. However, deep, fertile, well-draining but water retaining soil (can be achieved with plenty of organic matter) will give the biggest tubers. They do fine in big pots. I grew mine in old, repurposed water tanks.
The tubers can be planted from February to April, around 10cm deep and 30 cm apart. These do grow into big plants so do need some space as they can grow up to 10 feet tall. They make great living screens or do well in the back of a bed as they can still reach the sun. They can also be cut back and kept at 5 feet tall if that suits your space better. This also discourages flowering. If you do get flowers it is best to cut them back so that plant can put that energy into producing tubers. I have also read advice about earthing up the soil up the stem to support it and for better tubers. To be honest this plant is done very well despite my neglect. The only thing I did was shove the plants in very big pots and then stake with a bamboo cane when they got tall. I have run a dripper watering system through the garden (saves time as well as water – which you can read about here) so that was taken care of. However, don’t underestimate overcast days and strong winds. I made the mistake of turning the water off when the sun disappeared, and I lost one of my Jerusalem artichokes. We ate them anyway, but the tubers were much smaller and drier (shown in the very first photo at the top of the page).
How to harvest
It is best to leave this plant for as long as possible to get the biggest tubers. The leaves will start to go yellow and die as the weather gets cold. In this particular year (in London, UK) it was mid-November. You pull the stem up and some of the artichokes will come with it but really you will need to dig. Any plants you want to leave for later harvest, you can cut the stem back to a short stump and then leave the tops over the soil to keep it warm. They are fine to remain there even into December (as long as the soil isn’t waterlogged, and the ground doesn’t freeze). Once harvested they store in the fridge in a covered bowl fine for a week.
How to eat
The tubers have a thin skin that do not need to be peeled. The dirt should be carefully washed away though. If you would like to peel them, you can use just a spoon to scrape away the top layer and any bits you don’t want. Be aware that they do discolour very quickly so have a bowl of lemony water ready to receive them.
They can be eaten raw or cooked. Raw they have a texture and taste a bit like water chestnuts, with a nuttiness and a very slight taste of artichoke hearts. I like them roasted with garlic and rosemary or thrown in with a roasting chicken. They take on flavours well and the inside becomes very soft like potatoes do, but silkier rather than floury. I feel they lose the nuttiness with cooking but acquire this sweet, artichoke heart-y, potato-y taste. If you do roast them, if you make sure they are not touching their skins can gain a bit of crispiness.
I thought I’d best put this in as my other half had a bad night after eating a few too many. Like yacon, Jerusalem artichokes contain inulin, which is a sugar that humans cannot digest. It is a prebiotic (not a probiotic) that feeds the flora in the gut (as opposed to repopulating the gut). It’s good for your digestive system, but it can cause bloating and flatulence if you eat too much, too quickly. Apparently, your digestive system can adjust if you can introduce it slowly.