52 · Plant Guide by Role
The right plant in the right place does more work than any filter. Here are the top performers by function.
Marginals (bog shelf, 0–30 cm)
- Iris pseudacorus — yellow flags, vigorous, great for new ponds.
- Cattail (Typha) — architectural, wildlife magnet, needs containment.
- Marsh marigold (Caltha) — early spring colour, native.
- Water mint (Mentha aquatica) — fragrant, spreads fast, good for bees.
Submerged / oxygenators (below surface)
- Hornwort (Ceratophyllum) — no roots, free-floating, excellent nutrient sponge.
- Elodea / Egeria — fast-growing, oxygenates heavily, can clog pumps.
- Bladderwort (Utricularia) — carnivorous, eats mosquito larvae.
Lilies (deep water, 40–100 cm)
- Nymphaea alba (hardy white) — native, shade-giving, classic.
- Nymphaea marliacea (hardy yellow/pink) — reliable bloomer.
- Tropical lilies — vivid colours, need warm water, lift in autumn.
Floating (surface)
- Water lettuce (Pistia) — fast nutrient uptake, tender annual in cold climates.
- Water hyacinth — beautiful but invasive in warm regions; check local bans.
- Frogbit (Hydrocharis) — hardy, small lily-like pads, native to Europe.
Planting ratios
Aim for roughly 60% marginal shelf, 20% deep water, 10% oxygenators, 10% surface floaters. This mix absorbs nutrients from every zone and leaves algae no foothold.
Buy local
Source plants from native nurseries where possible. Avoid dumping aquarium leftovers into ponds — they may carry disease or invasive genetics.
Plant placement procedure
- Start with oxygenators — 3–5 bunches per 1,000 litres. Place in the deepest zone.
- Add marginals around 60% of the perimeter on shallow shelves.
- Place water lilies in the deep zone with the crown 300–600 mm below the surface.
- Add floating plants last — water lilies, water hawthorn, frogbit.
- Cover 50–60% of the surface by midsummer. Leave 40% open for gas exchange.
Plant maintenance by type
- Marginals: Divide every 2–3 years when they outgrow their baskets.
- Oxygenators: Remove half the bunches if they cover the entire bottom.
- Water lilies: Remove yellowing leaves promptly. Fertilise aquatic tabs in spring.
- Floating: Thin aggressively — duckweed doubles in 3 days in warm weather.