How to Grow Four-angled Glasswort

Wikimedia Commons

Four-angled Glasswort

Arthrocnemum tetraquetra

herb

A succulent halophyte (salt-loving plant) native to Mediterranean and North African salt marshes and coastal regions. This compact, shrubby plant features distinctive four-angled, jointed stems that are fleshy and bluish-green, with minimal true leaves. It is highly valued in coastal and saline gardening for its unique architectural form and exceptional salt tolerance.

When should you plant Four-angled Glasswort in your zone?

Get a personalized planting timeline — when to start seeds, transplant, and harvest — based on your USDA zone and local frost dates. Free to start.

Get my Four-angled Glasswort timeline →

Example Four-angled Glasswort timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Four-angled Glasswort

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Four-angled Glasswort

    Around Jul 16

    ≈ 90 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Four-angled Glasswort dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 8+ hours daily; tolerates intense heat and coastal reflective glare
💧
Water: Very low water needs; drought-tolerant once established. Water sparingly during growing season, avoid overwatering. In cultivation, water only when soil is completely dry. Tolerates saline or brackish water; does not require fresh water.
📏
Spacing: 18 inches
📅
Days to maturity: 90-120 days (relatively slow-growing)
🌱
Planting depth: Plant cuttings 1-2 inches deep; seeds directly sown at soil surface with light misting

Soil

Type: Well-draining, sandy or gritty soil; salt-tolerant substrate preferred
pH: 6.5-8.0 (alkaline soils acceptable)
Amendments:
Coarse sand or perlite for drainage Gravel or small stones Minimal organic matter Optional: salt or saline irrigation for authentic conditions

Growing Zones

Find your zone →

Thrives in zones 9-11; requires frost-free conditions

9a 9b 10a 10b 11a 11b

Sign up free to see if Four-angled Glasswort grows in your zone — and get a personalized planting timeline.

Get my Four-angled Glasswort timeline →

Growth Stages

1

Propagation

3-4 weeks

Tiny green cuttings or germinating seeds with minimal root development

Use sandy seed-starting mix; mist lightly; maintain warmth (65-75°F); avoid waterlogging. Cuttings root in 3-4 weeks.

2

Establishment

4-8 weeks

Young plant develops jointed, angular stems; growth is slow; blue-green coloration becomes apparent

Provide bright light and excellent drainage; reduce watering to minimal; no fertilizer needed. Acclimate gradually to full outdoor sun.

3

Vegetative Growth

2-3 months

Plant fills out, stems elongate and branch; characteristic four-angled structure is clearly visible; dense, sculptural form develops

Water very sparingly; no feeding required. Prune lightly if necessary to maintain shape. Extremely low-maintenance once established.

4

Flowering

4-8 weeks

Tiny, inconspicuous flowers appear along jointed stems in late summer to early fall; flowers are greenish-yellow and mostly hidden within foliage

Continue minimal watering; no special care needed. Flowers are not ornamentally significant.

5

Maturity

Year-round

Established plant reaches full landscape size; architectural form is dense and well-defined; color deepens under stress conditions

Essentially maintenance-free; no watering except in extreme drought; no pruning unless desired. Extremely long-lived.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Plants requiring regular fresh water and moist soil Plants sensitive to salt spray or saline conditions Acid-loving plants (blueberries, rhododendrons) Heavy feeders requiring rich soils

Common Pests

  • Rare in outdoor cultivation; if present indoors, spray with neem oil or insecticidal soap; improve air circulation

  • Uncommon; increase humidity and air circulation; rinse with water if severe

  • Prevent via excellent drainage and minimal watering; remove affected plants; do not amend with rich compost

Uses

🍳

Edible Succulent Forage

Culinary

Tender young stems are eaten fresh or pickled as a salty delicacy in Mediterranean cuisines, particularly in salt marsh regions. They provide a unique, mineral-rich, crunchy texture and briny flavor. [source]

🏠

Ornamental Xeriscape & Coastal Gardening

Household

The distinctive four-angled stems provide strong architectural form in drought-resistant and seaside gardens, particularly in coastal landscapes where salt spray is present. Used in modern xeriscaping and habitat restoration. [source]

💊

Traditional Salt Marsh Remedy

Medicinal

In Mediterranean folk medicine, the succulent stems were traditionally used to treat salt deficiency and provide mineral supplementation. Modern use is limited but historical records suggest use in remedies for electrolyte balance. [source]

🦋

Coastal Ecosystem Support

Wildlife

Native to Mediterranean salt marshes, this plant provides food and habitat for specialized salt marsh fauna and supports restoration of degraded wetland ecosystems. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

A. tetraquetra is primarily ornamental; however, young stem tips can be harvested and eaten fresh or pickled (traditional in Mediterranean salt marshes) for a salty, succulent taste. Harvest sparingly to maintain plant form. Pinch off tips in early summer when tender and bright green. No formal harvest schedule; used as a specialty culinary forage.

Fun Facts

  • 🌱 The name 'Arthrocnemum' comes from Greek 'arthron' (joint) and 'kneme' (leg), referring to the jointed, four-angled stem structure that is unique among Mediterranean succulents.
  • 🌱 A. tetraquetra is a halophyte that actually thrives in saline conditions that would kill most plants; it can be irrigated with seawater or brackish water and survives in coastal salt spray environments.
  • 🌱 In Spain and parts of North Africa, this plant is known by traditional names like 'salicor' and was historically harvested as a crop for ash production (soda ash) used in glassmaking—hence 'glasswort.'

Gardening Terms

New to gardening? Learn about terms used in this guide:

Join 30,000 gardeners planning their gardens with LizPlants.

Get your personalized Four-angled Glasswort planting timeline

Tell us your zip code and we'll calculate exactly when to start Four-angled Glasswort seeds, transplant seedlings, and harvest — based on your USDA zone and local frost dates. Includes calendar reminders and printable task lists. Free to start.

Get my Four-angled Glasswort timeline →