Silybum marianum

Milk thistle, also known as blessed thistle or Marian thistle, is an annual heirloom with spiked foliage and soft purple blooms that carry centuries of history in herbal traditions. Believed to have been used since Roman times, milk thistle is native to the Mediterranean but is now naturalised across much of the world. The white mottled leaves are thought to symbolise drops of the Virgin Mary’s milk, giving rise to the plant’s common name and deep cultural roots in European herbalism.

This is a truly useful garden herb. The seeds are the most well known part, rich in silymarin, a compound revered for its liver protective properties. They have long been used in support of liver detox, gallbladder health, and to aid recovery from ailments such as jaundice, hepatitis and mushroom poisoning. Seeds are often brewed into teas or ground into tinctures, and even chewed straight to help clear a hangover. But the usefulness does not stop there. The roots can be cooked like carrots, flower spikes treated like artichokes, and young leaves, once the spiny edges are removed, add a unique note to salads.

Milk thistle is best grown in full sun with space to stretch. Rows spaced 40–75 cm apart, with plants placed 25 cm apart, will produce the healthiest growth. It thrives in poor soils with a wide pH tolerance from 5.5 to 7.6 and is drought tolerant once established. The spiky flower heads mature in about 70 days and should be harvested once around half have turned brown and dry. Wear gloves when handling the sharp seed heads and remove fluff before storage.