Photo: Ivar Leidus · CC BY-SA 3.0 ↗

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Wetland plantsWild and cultivated

Lythrum salicaria

Purple-loosestrife

Dense reddish-purple spikes rise along summer waterways; cultivated forms also appear in water gardens.

See all four seasons Explore fruits, seeds & edibility ↓ Where to look & how to find it ↓

Some plants are poisonous. Do not identify by a photograph alone, and never taste them.

FIELDCRAFT · FIND WITH CARE

Finding guide

Season first

Choose the season, find the habitat, then watch patiently. Search guidance is not a measure of rarity or conservation status.

When to go: Usually flowers June–September.
Where to start: Irish river and canal paths. Revisit the same stems in autumn and winter to see their dry remains.
What to do when you arrive: In summer, follow public waterside paths for tall purple-magenta spikes, checking leaf arrangement and flowers. Dead stems can be revisited later but may not support species identification alone.

Habitat and behaviour reference: Wildflowers of Ireland ↗ · The practical steps are editorial advice based on the references, not live sightings.

ONE PLANT · FOUR SEASONS

One plant. Four seasons.

Look beyond the flowers: fresh leaves, fruits, bare stems and dormancy.

Meteorological seasons: spring March–May, summer June–August, autumn September–November and winter December–February. Irish weather, cultivar, pruning and plant age affect timing and appearance.

Photos illustrate the relevant feature, not the same plant photographed through a year in Ireland. Features shared across seasons, such as evergreen leaves, may use the same reference. Missing reliable photos are marked; dormancy is not death.

Spring

Mar–May

Foliage and growth

Several upright new shoots emerge from the crown and expand narrow leaves.

Summer

Jun–Aug

Flowers

Dense reddish-purple flowers open along tall spikes in the main bloom period.

Autumn

Sep–Nov

Feature photo not yet availableUse the appearance notes below; a different seasonal stage is not substituted.

Seeds and spent flowers

Capsules set seed; leaves may redden or yellow as stems dry brown.

Winter

Dec–Feb

Bare branches or dry stems

Dry upright stems and small capsules may remain above the surviving perennial crown.

Seasonal references: Wildflowers of Ireland ↗ · Photo resized, converted to JPEG and stripped of metadata.

FRUIT · SEED · FOOD SAFETY

Fruits, seeds & edibility

Know the structure, then the part. Recognising a plant does not make it food.

Fruit

Numerous small brown capsules develop along the dense flowering stem.

Food use of this part: Food safety not established by this guide

Seeds & dispersal units

Purple-loosestrife · An opened purple-loosestrife capsule with tiny seeds. — An opened purple-loosestrife capsule with tiny seeds.
KrisMaes · CC BY-SA 4.0 ↗ License terms

Each capsule can hold many sand-sized seeds; avoid transporting and spreading them.

Food use of this part: Food safety not established by this guide

Some seed references show intact one-seeded fruits or dispersal units, as identified in their captions. A whole-fruit photo is not a close-up of the enclosed seed. Cones and arils are not true fruits of flowering plants.

Sources & limitations

Wildflowers of Ireland ↗ · Botanical description, not proof of food safety
NC State Extension · Plant Toolbox ↗

No field detoxification methods or safe doses are provided. Never taste a plant to identify it or eat treated or contaminated specimens. Seek professional help after suspected accidental ingestion. National Poisons Information Centre, Ireland ↗

Photo resized, converted to JPEG and stripped of metadata.

BOTANICAL NOTESPlant notes

How to identify it

Upright stems with lanceolate opposite or whorled leaves; small, usually six-petalled flowers with slightly crumpled petals.

Where it grows

Riverbanks, canals, ditches, marshes and water gardens.

Growth and ecology

A native Irish wetland perennial attracting insects. Its invasive status on other continents does not apply automatically to Ireland.

Flowering and seasons

Usually flowers June–September.

Where to look

Irish river and canal paths. Revisit the same stems in autumn and winter to see their dry remains.

Seasons vary with weather and location. Suggested habitats are places to look, not guaranteed sightings. Photos show only some features; check leaves, flowers, fruits and specialist references together.

Further reading:Wildflowers of Ireland ↗

Photo license: Ivar Leidus · CC BY-SA 3.0 ↗ · License terms ↗
Photo resized, converted to JPEG and stripped of metadata.

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