Marsh samphire (glasswort) Salicornia europaea
Marsh samphire (glasswort) (Salicornia europaea) is an annual vegetable in the Amaranthaceae family, native to Salt marshes and mudflats of Europe, North Africa and western Asia. It grows 10–35 cm (4–14 in) tall and 10–25 cm (4–10 in) wide, wants full sun and high water, and is hardy to about -5 °C (23 °F). Space plants about 10 cm (4 in) apart.
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Marsh samphire (glasswort) at a glance
| Type | Annual vegetable |
|---|---|
| Family | Amaranthaceae |
| Mature height | 10–35 cm (4–14 in) |
| Mature spread | 10–25 cm (4–10 in) |
| Spacing | 10 cm (4 in) centre to centre |
| Sun | Full sun, at least 7 h of direct sun a day |
| Water | High; drought tolerance none, waterlogging tolerance high |
| Soil pH | 6.5–9 |
| Cold hardiness | About -5 °C (23 °F) once established (roughly USDA zone 9) |
| Heat stress | Likely above about 35 °C (95 °F) |
| Flowering | about 14–19 weeks after planting, for 4–6 weeks |
| Days to maturity | About 90 days from planting |
| Wind tolerance | High |
| Pollinator value | None |
| Edible | Yes: succulent green stems (raw, steamed, pickled) |
| Native to | Salt marshes and mudflats of Europe, North Africa and western Asia |
| Common in gardens of | 🇬🇧 United Kingdom, 🇫🇷 France, 🇳🇱 Netherlands, 🇩🇪 Germany, 🇮🇪 Ireland, 🇺🇸 United States, 🇮🇱 Israel |
Is Marsh samphire (glasswort) toxic?
- People: not known to be toxic
- Cats: not known to be toxic
- Dogs: not known to be toxic
Not poisonous; naturally very salty.
If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.
Companion planting: what to grow with Marsh samphire (glasswort)
No well-documented helpful pairing. Group it with plants that like full sun and high water.
Questions about Marsh samphire (glasswort)
- How far apart should I plant Marsh samphire (glasswort)?
- About 10 cm (4 in) apart, centre to centre. A mature plant spreads 10–25 cm (4–10 in).
- Does Marsh samphire (glasswort) need full sun?
- Full sun: at least 7 hours of direct sun a day.
- How much water does Marsh samphire (glasswort) need?
- High water. Drought tolerance is none and waterlogging tolerance high.
- How cold-hardy is Marsh samphire (glasswort)?
- It tolerates about -5 °C (23 °F) once established, roughly USDA zone 9. As an annual it is usually planted out after the last frost.
- When does Marsh samphire (glasswort) flower?
- About 14–19 weeks after planting, for 4–6 weeks.
- Is Marsh samphire (glasswort) poisonous to cats and dogs?
- For cats it is not known to be toxic; for dogs not known to be toxic; for people not known to be toxic. Not poisonous; naturally very salty.
- What grows well with Marsh samphire (glasswort)?
- There is no well-documented companion pairing for Marsh samphire (glasswort). Group it with plants that like the same sun (full sun) and water (high).
Sources and evidence
Evidence grade B (B: extension service or peer-reviewed).
- Plants of the World Online (taxonomy, native range), Royal Botanic Gardens, Kew
- Plants For A Future database, PFAF
- Wildflowers and meadows, Plantlife (UK)
Notes and assumptions
- Leafless, jointed, fleshy stems that turn red in autumn. A halophyte: it needs salty, tidal mud or seawater-irrigated beds, so ordinary garden soil does not suit it. Ash of glassworts was once burnt for soda in glass and soap making.
Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.
Related plants
- Spinach Spinacia oleracea
- Swiss chard Beta vulgaris subsp. vulgaris (Cicla)
- Beetroot Beta vulgaris subsp. vulgaris
- Amaranth (leaf, callaloo) Amaranthus tricolor
- Quinoa Chenopodium quinoa
- Love-lies-bleeding (kiwicha) Amaranthus caudatus
- Epazote Dysphania ambrosioides
- Celosia (cockscomb) Celosia argentea