Bunium bulbocastanum

The Earth Chestnut or Earthnut, in Latin Bunium bulbocastanum, is a perennial plant native to the European countryside, whose edible tubers had been consumed since the Bronze Age, before the discovery of the potato. Today we are rediscovering the delicate flavour of this ancient and forgotten vegetable, halfway between chestnut and potato. In the garden, we can enjoy its charm for a few years before uprooting it for harvest: its finely cut and aromatic foliage can be used like parsley, and its pretty umbels of white flowers give way to seeds that can be used as an alternative to cumin.

Bunium bulbocastanum belongs to the Apiaceae family (formerly Umbelliferae), like celery, carrot, and fennel. This wild plant is native to Western, Central, and Southern Europe, and North Africa, but its distribution area extends north to England, Germany, the Netherlands, and Slovenia. In nature, it is sometimes found on forest edges or in some meadows. It is a very hardy species that appreciates clay/limestone soils but is sensitive to excess water.

Bunium bulbocastanum is a perennial plant, herbaceous from its stump, whose roots produce small edible tubers that serve as reserve organs to withstand periods of scarcity. The aerial vegetation generally persists in winter, depending on the climate. The plant forms a clump 50 to 60 cm (20 to 24in) tall when flowering and 40 cm (16in) wide. Its growth is quite slow: slender stems emerge from the stump, becoming more numerous over the years. The basal leaves, carried by a long petiole, are finely divided into numerous narrow and linear segments, they are aromatic and bright green, giving the plant a light appearance. Flowering occurs in June-July, depending on the climate. The floral stems, which bear a few rare leaves, produce a dense and pure white, hairy umbel, composed of small flowers with protruding stamens, much visited by pollinating insects. After pollination, they give way to numerous small dark crescent-shaped seeds. Underground, the roots form a dense network of root hairs where the nuts or ground chestnuts, measuring 1 to 2 cm (1in) in diameter, develop.

A wild plant appreciated for the natural and light touch it brings to a flowerbed, among bushes, roses, or other perennials, Bunium bulbocastanum is easily cultivated in any garden soil, limestone or clay, moist to occasionally dry. Perfectly adapted to our climates, it brings essential biodiversity to the garden. You can also plant it in the vegetable garden, where it will appreciate enriched and well-worked soil, as well as regular watering.

In the kitchen:

• The leaves, raw or cooked, can be used like parsley to flavour salads, cooked dishes, stuffed vegetables, and winter soups.
• The seeds, formerly known as black cumin, have a flavour similar to cumin.
• The tubers can be eaten raw or cooked, mashed to accompany roasted meats, or in soups of foraged vegetables.