Alisma plantago-aquatica - Water Plantain, Native Pond Marginal Plant

Alisma plantago-aquatica, known as water plantain, is a UK native marginal plant with rosettes of oval, grey-green leaves. From June to September it sends up tall, branching sprays of small white flowers, which open in the afternoon.

Water plantain at a glance

Botanical name	Alisma plantago-aquatica
Common name	Water plantain
Plant type	Clump-forming perennial; dies back in winter
Height and spread	Usually 45–60 cm tall in flower (RHS: up to 1 m), up to 50 cm wide
Flowers	Small, white to pale lilac, in tall airy sprays, June to September
Position	Full sun or part shade
Soil	Wet mud or shallow water
Pond depth	10–20 cm of water over the crown (up to 30 cm)
Hardiness	RHS H7 – very hardy (below -20°C)
Native to	UK and Ireland (native wild flower)

Where to plant water plantain

Pond shelves with 10–20 cm of water over the crown
Wildlife ponds and natural pond margins
Larger ponds and lakes

Is water plantain good for wildlife?

Yes. It is on the RHS Plants for Pollinators list and is visited by small flies, bees and hoverflies. Seed heads left over winter feed birds, and the dead stems shelter aquatic insects.

Does it self-seed?

Yes, freely. Cut off the flower stems once flowering finishes if you do not want seedlings around the pond.

Is water plantain poisonous?

Yes. The leaves and roots are toxic and the sap can irritate skin, so wear gloves when handling it.

Which size should I buy?

Bare-root plants (7 cm, 9 cm, 1 litre and 3 litre) arrive without a pot or compost and are the most economical way to plant a group. Potted plants (9 cm, 1 litre and 3 litre) arrive growing in our peat-free compost and give a faster display. Packs of 3 cost less per plant. The 2x Pot & Compost option is two plants supplied with pots and compost.