Aponogeton (water vanilla): the plant that blooms when water lilies sleep, cultivation and tips

In spring, before the water lilies wake up, and again in autumn when they decline, one plant brightens the pond with sweetly scented white flowers: the two-spiked aponogeton, nicknamed water vanilla. It is one of the few floating plants that flower in the cool season, making it the perfect companion to water lilies.

Identity card

A rhythm opposite to that of water lilies

In its native habitat, Aponogeton grows in ponds that fill in winter and dry out in summer. It has retained an offset cycle: it grows and flowers when the water is cool, then slows down or even loses its leaves when the water warms up. So don't worry if you see it withering in July: this is a normal summer dormancy, and it starts growing again as soon as the nights cool down. In a pond shaded in the afternoon or supplied with cool water, it may even flower almost all year round.

This shift in timing is what makes it valuable: paired with water lilies, it provides flowers on the water from spring to late autumn.

Planting

1. In spring, as soon as the water warms up.
2. In a medium-sized openwork basket, lined with burlap if the mesh is wide.
3. In heavy aquatic soil, never garden soil.
4. Tuber barely buried, shoots facing upward, covered with a layer of gravel to prevent fish from digging.
5. Gradual lowering: first place the basket at a shallow depth, then lower it to 30 to 60 cm as the leaves reach the surface.

Care and fertilization

Water hawthorn requires very little. Remove faded leaves and flowers to keep the water clean. In spring, push a slow-release fertilizer tablet into the basket, as close to the roots as possible: the plant benefits from it, while the water benefits much less, preventing algae from being fed. Every three or four years, take out the basket and divide the tubers if the plant has spread.

Winter

In our regions, water hawthorn can spend the winter outdoors without any problem if planted deep enough. In small ponds that freeze deeply, lower the basket to the deepest point in autumn. During mild winters, it is not unusual to see it retain its leaves and even flower in December or February.

Successful combinations

Plant it next to a medium-sized water lily: one takes over from the other. It also pairs very well with oxygenating plants such as hornwort, and spring marginal plants such as marsh marigold, whose yellow flowers contrast with its white ones. A curious fact: in South Africa, its flower buds are traditionally cooked in stews.

Common problems and their solutions

Aponogeton also readily self-seeds: its seeds fall to the bottom and sometimes germinate in neighboring baskets. The young plants can be identified by their small floating leaves and are easy to repot in spring to expand the colony or give away.

Also read

Choosing the right container for your plants: Use slotted baskets rather than conventional pots.

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Frequently asked questions

— My aponogeton loses its leaves in summer; is it diseased?

No, this is its summer dormancy. It starts growing again when the water cools at the end of summer.

— Can it be grown in a small pond?

Yes, provided there is at least 30 cm of water above the basket and an area that does not freeze to the bottom.

— Do fish eat it?

Goldfish generally leave it alone. Koi may rummage through the basket: protect the substrate with gravel.

— Can it be grown in a container on a terrace?

Yes, in a large container at least 40 cm deep, placed in partial shade to limit summer warming. In winter, move the container closer to a sheltered wall or protect it from frost, as a small volume freezes much faster than an in-ground pond.

— Is it invasive?

No, it remains contained in its basket and divides easily.

In summary

• Fragrant white flowers in spring and autumn.
• 30 to 60 cm of water above the tuber, sun to partial shade.
• Normal summer dormancy when the water warms up.
• Hardy if the tuber remains below the frost line.

Last updated: September 28, 2026.