Salicornia europaea aka Common Glasswort

Salicornia europaea, or glasswort, is an annual in the Amaranthaceae family. Kew gives its native range as northern and western Europe. The RHS confirms that it is native to Britain and Ireland. It grows in temperate climates and can withstand exposed coastal sites. Its wild habitats include coastal sand, mudflats, and salt marshes. Plants often grow close to the low-tide mark.

Glasswort reaches about 1 foot [0.3 metres] in height. Its size and number of branches vary a great deal. Bushy, upright plants can reach 1.3 feet [0.4 metres]. These forms suit food production because branches stay above the mud. The stems are fleshy, with a narrow, woody core inside. That core is easy to remove when preparing the stems. The plant flowers in August, and seeds ripen in September. Each flower has both male and female organs. Wind carries the pollen.

Glasswort needs an open site without shade. It accepts sandy, loamy, and clay soils. It also grows across mildly acid, neutral, and alkaline conditions. It can cope with very alkaline ground and salty soil. PFAF lists dry or moist soil as suitable. Its growing notes favour rich soil, ample nitrogen, and regular watering. Yet its exact needs in gardens remain poorly understood. It is unclear whether periodic flooding with salt water helps growth. PFAF describes it as difficult to grow in cultivation. Sow ripe seed outdoors in autumn, in a well-drained bed.

Young stems can be eaten raw or cooked. They have a salty taste and need little cooking. Add them to soup near the end of cooking. Late summer is the best harvest season. Shoots about 0.5 feet [0.15 metres] long suit picking. Take the upper part and leave the base to regrow. Young shoots can also be boiled and then pickled. PFAF lists leaves and seeds as edible parts too.

Its garden use includes growing in cultivated beds for food. Beyond food, its ash provides potash for soap and glass making. The ash itself can also serve as a cleanser. PFAF records no known hazards and no known medicinal uses. This does not establish safety for every use. The supplied sources give no specific pest or disease problems.