Tripolium spp.

sea aster

Asteraceae

Europe, North Africa, and temperate Asia

Attracts Pollinators Attracts Butterflies

SunFull Sun

WaterHigh

HardinessZones 5–9

Overview

Tripolium spp. is a genus in the daisy family (Asteraceae) consisting mainly of the sea aster, Tripolium pannonicum, a halophyte of coastal marshes across Europe, North Africa, and temperate Asia. Plants are annual to short-lived perennial herbs forming upright, branched stems 8-32 inches (20-80 cm) tall. The leaves are fleshy, narrow, and lance-shaped, an adaptation to salt-laden soils, and are arranged alternately along the stems. Flower heads, 0.4-0.8 inch (10-20 mm) across, are carried in loose, branched clusters; each head has lilac to pale-purple ray florets surrounding a yellow disc, though a rayless form occurs in some populations. Blooming runs through late summer and autumn, and the seeds bear a pappus of hairs that aids wind dispersal. The genus occupies salt marshes, estuaries, tidal mudflats, and inland saline soils, tolerating periodic flooding by brackish water. The young leaves and shoots are edible and are harvested as a coastal vegetable. Its salt tolerance limits competition, allowing it to colonise ground where few other flowering plants persist.

Native Range

Native to coastal and inland saline habitats across Europe, North Africa, and temperate Asia, from the Atlantic and Mediterranean coasts eastward to central Asia.

Suggested Uses

Grown in coastal and seaside gardens, salt marshes, and rain gardens with saline or brackish soils. The young leaves and shoots are also cultivated as an edible vegetable.

How to Identify

Fleshy, narrow lance-shaped leaves and branched, upright stems mark this salt-marsh daisy. Flower heads 0.4-0.8 inch (10-20 mm) wide carry lilac to pale-purple rays around a yellow disc, with a rayless form in some populations. Seeds carry a tuft of pappus hairs.

Appearance

Size & Dimensions

Height8" - 2'8"

Width/Spread1' - 2'

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~12 weeks

Summer Fall

Flowering runs from midsummer into autumn, roughly July to October. The lilac-rayed heads open in succession across branched clusters. Seed heads with downy pappus follow, releasing wind-borne seed through autumn.

Detailed Descriptions

Flower Description

lilac to pale purple with yellow centre

Foliage Description

fleshy green to grey-green

Growing Conditions

Sun Requirements

SunFull Sun

Requires 6-12 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range6.0 - 8.0(Neutral)

357912

Soil Types

clay sand silt

Drainagewet

Water & Climate

Water Needs

High

Frost Tolerance

hardy

Care & Maintenance

Care Guide

Sea aster grows in full sun in moist to wet soils and tolerates high salinity that excludes most garden plants. It accepts clay, silt, and sandy soils provided they stay damp, and withstands periodic tidal or brackish flooding. In cultivation it grows readily from seed sown in autumn or spring and needs little feeding. As an annual to short-lived perennial, plants may be left to self-seed to maintain a stand. Aphids occasionally gather on young shoots but rarely cause lasting harm.

Pruning

No formal pruning is required. Stems can be cut back after seed dispersal in autumn, and self-sown seedlings thinned where spread is unwanted.

✓ Toxicity

Non-toxic

Perennial

Tripolium spp.

sea aster

Asteraceae

Europe, North Africa, and temperate Asia

Attracts Pollinators Attracts Butterflies

SunFull Sun

WaterHigh

HardinessZones 5–9

Overview

Native Range

Native to coastal and inland saline habitats across Europe, North Africa, and temperate Asia, from the Atlantic and Mediterranean coasts eastward to central Asia.

Suggested Uses

Grown in coastal and seaside gardens, salt marshes, and rain gardens with saline or brackish soils. The young leaves and shoots are also cultivated as an edible vegetable.