Jerusalem artichoke is popular as a “functional food” and healthy, high-fiber potato substitute. When it comes to growing vegetables, however, the question arises: when and how should you harvest Jerusalem artichokes?
Jerusalem artichoke (Helianthus tuberosus), also known as sunchoke, is a sunflower, native to North and Central America, from the composite family (Asteraceae) and is grown for the high-quality ingredients in its tubers. It is called “functional food” because it has not only nutritional value, but also health value. Its tubers, protected in the ground, can withstand temperatures as low as minus 30 °C / -22 °F.
The plant forms towering bright yellow flower heads above ground and many tubers about the size of a potato in the soil. These are similar in appearance to ginger, as they are also surrounded by a brownish skin. While ginger is usually peeled before processing, this is not absolutely necessary with Jerusalem artichokes because of the thinness of the skin.
Depending on the variety grown, you can always harvest them fresh during frost-free periods between October and March. If you mulch the soil around the plants with leaves or straw, you prevent ground frost and the Jerusalem artichoke harvest in the garden is thus possible almost throughout the winter.
The taste of Jerusalem artichoke tubers is reminiscent of parsnip with a pleasant nutty and artichoke-like note. Like many of useful plants, Jerusalem artichokes arrived in Europe with seafarers from North America in the 17th century. Jerusalem artichoke quickly established itself as a delicacy, especially in Parisian haute cuisine, until it was supplanted by the potato in the 18th century. But now the delicious tuber is rightly experiencing a revival in the kitchen. Whether cooked, braised, roasted or raw – there are numerous ways to prepare Jerusalem artichokes.
Jerusalem artichoke – What you need to know
Jerusalem artichoke: When is the inulin content highest?
The most important ingredient from a nutritional point of view in Jerusalem artichoke is the polymer inulin. This long-chain sugar is not absorbed in the small intestine and acts as a dietary fiber. Only in the large intestine is inulin converted into short-chain fatty acids: This means that by eating Jerusalem artichoke, fat levels in the blood can be lowered, and at the same time the desirable bifidus population increases in the intestine. Those who value the highest possible inulin content of the tubers should harvest them as early as October, because then the content is over 70 percent of the dry matter, and in the following spring more at 50 percent. The fructose content, which was positively assessed, decreased in particular, while the total sugar content remained the same.
Harvesting Jerusalem artichokes: How to do it properly
The wilting and browning leaves show it at the latest after the first frosty night: The Jerusalem artichoke in the garden is ready for harvest. Whether to take the tubers out right away or leave them in the ground, that can be decided on a case-by-case basis.
Before harvesting, cut off the shoots above the ground, the best way to do this is with garden shears. For the actual lifting out, use a digging fork, with which, as with potatoes, you carefully poke under the tubers and then lift them up. At the same time, you can grab the cut shoots with your other hand and pull.
Important: But one tuber is always left in the ground, so that the continuity of the crop is ensured. The tubers are then plucked from the roots, and the shoot residues are removed. Before using the vegetable crop is brushed off, only very dirty tubers can be peeled. Where a tuber has been injured with a fork, brushing with lemon juice prevents the tissue from turning brown.
Caution: Trouble at harvest time can be voles, which also like to eat the nutritious tubers. Where they are up to mischief, get the tubers out of the ground promptly and pound them in moist sand. Alternatively, they can be placed in a bucket together with the soil.
How to store Jerusalem artichoke
Regardless of the time of harvest: Sunchoke should be consumed as fresh as possible after harvest. The reason for this is the thin skin, which is unsuitable for longer storage because it dries out quickly.
But there are many ways to prepare it: Jerusalem artichoke tastes good as a raw vegetable in a salad, soup, like fried potatoes or gratin. The beauty of Jerusalem artichoke is that once it is grown, you can harvest steadily. This is because it is a perennial that also looks very attractive with its many small sunflower blossoms.
Not only the tubers of Jerusalem artichoke can be eaten. Also the young bleached shoots taste delicious in the spring, if you pile them like leeks over the winter.
Peel Jerusalem artichoke: the best way to do it
First, you should scrub Jerusalem artichoke tubers with a vegetable brush under cold water to remove adhering soil. The surface is often uneven and a bit knobby or crinkly, making peeling difficult.
One way to remove the fine skin is to use a peeler. However, depending on the model, much of the delicious tuber can be lost in the process. Alternatively, you can use a small sharp and pointed knife. This allows you to work more precisely and even reach the places where the peeler does not reach. If a tuber is very branched, peeling works better if you first cut it into sections. Peeling is even easier and particularly economical with a spoon. To do this, rub the edge of a teaspoon or tablespoon over the root tubers until the outer layer is completely removed.
To prevent Jerusalem artichoke from turning brown, sprinkle it with a little lemon juice immediately after peeling or store it in a bowl of cold water until further processing.
Peel Jerusalem artichoke after cooking
You can also remove the peel after cooking, but this is usually even more tedious and therefore not necessarily advisable. Depending on the recipe and how soft you want the vegetable to be, boil the washed Jerusalem artichoke in a pot of water for 10 to 30 minutes. After that, let it cool briefly and then peel it with a knife.
Do you have to peel Jerusalem artichokes at all?
The brown to slightly purple skin is thin, tender and edible, so you can eat it without hesitation. In this case, simply clean the Jerusalem artichoke tubers thoroughly with a vegetable brush in cold water and remove dark spots with a knife.