Jerusalem Artichoke is a plant that usually grows wild, but can also be cultivated. It’s also known by names like sunchoke, wildsunflower, topinambur, or earth apple. As you can easily guess, it’s a very hardy plant, which makes cultivating it a straightforward practice. As some of its common names suggest, it originates from Canada. For years, it was cultivated for food purposes by various peoples of North America. It was brought to Europe through the early transoceanic voyages and over time, it spread everywhere. In Italy, it grows vigorously almost everywhere: along watercourses, in uncultivated fields, along the edges of country roads. All it needs is plenty of sunlight. It’s harvested in early autumn and due to its widespread distribution, its tubers are easy to find. Autumn is also the right time to start cultivating it.
So, let’s get to know the botanical characteristics of Jerusalem Artichoke, how to cultivate it in our home garden, its nutritional properties, and its culinary uses.
Botanical Overview of Jerusalem Artichoke
Jerusalem Artichoke, scientifically known as Helianthus tuberosus, belongs to the family Asteraceae or Compositae. It’s a close relative of the sunflower, sharing some of its characteristics. The name Helianthus comes from the combination of two Greek words, namely helios = sun and anthos = flower, indicating the flower’s ability to follow the movement of the sun, just like the sunflower. Both wild and cultivated varieties of Jerusalem Artichoke have edible tubers, which are the specialized roots.
Characteristics of Jerusalem Artichoke
Jerusalem Artichoke is a perennial herbaceous plant, and its prized and edible part is the root. The tubers are irregularly shaped and knobby, with a tough and consistent skin that’s brownish-yellow in color. They’re quite large, usually up to 10 cm long and 6 cm wide. The root is highly branched, with numerous tuber-bearing rhizomes branching from the main tuber. The tubers start growing to a significant size after flowering, from August to October, which is the ideal time for harvesting. Externally, Jerusalem Artichoke presents a long stem that can reach up to 3 meters in height. It’s branched in the upper part, bearing numerous flowers. The leaves are long and narrow, with dark green color on the upper side and grayish on the lower side. They have a rough texture. The flowers, yellow in color, resemble those of the sunflower, albeit much smaller. Their diameter typically ranges from 4 to 10 cm. The inflorescence is a capitulum and, as mentioned earlier, follows the sun’s movement, a phenomenon known as heliotropism in nature. Flowering is distinctive and vibrant, occurring in late summer and lasting until the plant dries out. The plant dries up with the arrival of the first frosts, in November or December. After flowering, the plant goes dormant, but in spring, new shoots will emerge from the underground tubers, and its vegetative cycle will restart.
Harvesting and Starting a New Jerusalem Artichoke Cultivation
Starting a Jerusalem Artichoke cultivation often coincides with the harvest. Tubers from wild plants are collected in autumn, and it’s during this period that a new cultivation can begin. Alternatively, if wild plants are not available, tubers can be obtained from specialized stores or well-stocked grocery points. Harvesting Jerusalem Artichoke involves loosening the tuber from the soil, perhaps using a shovel or fork for assistance. Naturally, care must be taken not to damage the tuber during this operation. On light and loose soil, you can harvest by uprooting the plant and its tubers by hand.
Domestic Cultivation of Jerusalem Artichoke
Cultivating Jerusalem Artichoke is a straightforward process for several reasons. Firstly, due to its climate and soil requirements. Jerusalem Artichoke is a very hardy plant. It’s not sensitive to cold since the tubers are underground, and it’s not prone to drought (it doesn’t need irrigation). It adapts well to various types of soil, except for those that are very clayey and compact. It doesn’t require any type of fertilization, not even light. Another aspect of its hardiness is that it’s not attacked by pests; in fact, they tend to stay away. So, it’s just a matter of performing a classic soil preparation, for example with a simple shovel, to break up the main clumps to a depth of 20-30 cm. Then, bury the tubers at a depth of about 10 cm. A distance of at least 20-25 cm should be maintained between one tuber and another. The rows, on the other hand, should be kept at a distance of at least 50 cm from each other. The tuber remains dormant in the soil throughout the winter, and in spring (between March and April), new shoots emerge from the ground, restarting the vegetative cycle.
Some Tips for Jerusalem Artichoke Cultivation
Here are some practical tips for successful Jerusalem Artichoke cultivation. Firstly, avoid planting tubers in frozen soil: while they can withstand the cold, it’s better to avoid starting on overly challenging terrain. It might be better to anticipate the arrival of frost. If you’re running late, you can postpone the start of cultivation until spring by keeping the tubers in damp sand in a cool place. Another suggestion is to divide the larger tubers before burying them, ensuring they each have at least one viable bud (eye). This operation is similar to what’s done in the potato planting, turmeric, or planting processes. Another important tip is to choose a portion of the garden where Jerusalem Artichoke can grow over the years without disturbing future plantings. Jerusalem Artichoke is quite invasive due to its strong ability to propagate from unharvested tubers. Ideally, bury the tubers in a raised bed enclosed by a cement edge to easily control its spread. Additionally, note that Jerusalem Artichoke is an ornamental plant, which can influence its placement in the garden. Lastly, keep in mind that approximately 150 g of seed tubers are sufficient to cultivate a square meter of land. From one square meter of cultivated land, you can harvest around 2-3 kg of tubers.
Nutritional Properties of Jerusalem Artichoke
Jerusalem Artichoke is a food with excellent nutritional properties. It’s very low in calories, only 30 Kcal per 100 g of product, but at the same time, it’s rich in inulin. According to the book Anti-cancer antioxidant foods. Eat well to prevent and fight disease, written by scientists Jhoannes F. Coy and Maren Franz, these characteristics make Jerusalem Artichoke a suitable food for those with diabetes. Additionally, inulin is said to provide a favorable environment for the development of intestinal bacterial flora. This makes Jerusalem Artichoke a tuber vegetable that might be recommended for individuals with digestive issues. Other components of Jerusalem Artichoke tubers include water (about 80%), carbohydrates (including 15-20% fructose), fiber, vitamin A, B-group vitamins, minerals (iron, potassium, silicon, phosphorus, magnesium), and amino acids (asparagine and arginine). Jerusalem Artichoke is also a source of biotin (vitamin H), which is essential in alleviating physical fatigue, muscle pain, and loss of appetite. Lastly, it’s a food that promotes lactation in breastfeeding mothers, as the tuberized roots are galactagogues.
Jerusalem Artichoke in the Kitchen
Jerusalem Artichoke is the star of various recipes and is used in cooking much like potatoes. It can be boiled or steamed to create simple and tasty side dishes. It can also be pan-fried or baked in the oven. After cooking, the tubers have a delicate and slightly sweet flavor, somewhat reminiscent of artichokes. Jerusalem Artichoke can also be used raw, grated directly onto the dishes you want to season. Of course, this is only possible if the Jerusalem Artichoke comes from organic cultivation. It’s worth noting that the outer skin of the tuber is also edible, as it’s very digestible. Therefore, there’s no need to spend time peeling the skin. One minor drawback is that Jerusalem Artichoke tubers, once harvested, don’t keep for very long. They need to be stored in the refrigerator in paper bags and consumed within a maximum of 10 days.