In a previous article I wrote about how marginal plants are the “walls” of your pond, using the same logic you could easily say that Water Lilies (Nymphaea) are the “rugs.”
As pond plants go, in my opinion they are the crown jewels of any water garden, known for their iconic floating leaves and stunning, symmetrical blooms often in very vibrant and punchy colours.
Unlike marginal plants that will sit on the edge of your pond, water lilies are Deep Water Plants and sit in (Zone 4). Their roots will stay at the bottom, while their leaves (pads) grow on long, flexible stalks to reach the surface. Some plants will even accept a water depth reaching an impressive 1.5 metres.
The Two Main Varieties
When you go shopping for lilies, you will have two very different categories to choose between:
- Hardy Lilies: These are the “set and forget” types. They survive the winter by going dormant at the bottom of the pond. They bloom during the day and come in shades of white, yellow, pink, and red.
- Tropical Lilies: These act like annuals in cooler climates (unless brought indoors). They come in “electric” colors like blue and purple, have larger flowers, and are often much more fragrant. Some varieties even bloom exclusively at night.
Why They Are Essential
Water lilies are vital for a balanced pond ecosystem and do much more than just look pretty;
- Algae Control: By covering large parts of the surface of your pond, they block sunlight from reaching the water. Since algae need light to grow, lilies are a fantastic line of defense against “green water.”
- Fish Protection: The wide pads provide a sheltered zone for fish, giving them a place to hide from predators like herons or cats.
- Temperature Regulation: On hot summer days, the shade from the pads will help to keep the water temperature from spiking too high in your pond, which in turn also helps to maintain the oxygen levels for your fish.
Maintenance & Planting
To keep a lily happy, you need to manage its growth:
- The 50% Rule: When setting up your pond, you should aim for lilies to cover approximately 50% to 60% of your pond’s surface. If they cover 100%, then unfortunately your fish won’t get enough oxygen; if they only cover 10%, you’ll end up getting green water and algae.
- Planting Depth: Most hardy lilies prefer to sit 30cm to 90cm (1 to 3 feet) deep.
- Still Water Only: Lilies hate “wet leaves.” They should never be placed directly under a waterfall or fountain spray. Constant splashing will rot the pads and eventually kill the plant.
- Heavy Feeders: Lilies are hungry! To get big blooms, you usually need to push “aquatic fertilizer tabs” into the soil of their basket once a month during the growing season.
A Word of Caution: Nymphoides
Be careful not to confuse true Water Lilies with “Fringed Water Lily” or “Water Snowflake.” These are beautiful but can be incredibly invasive. In a small pond, they can go from one pretty leaf to a tangled mess that covers the entire surface in a single season.
Common “Beginner” Varieties:
- ‘James Brydon’: A classic deep red that handles a bit of shade better than most.
- ‘Chromatella’: A beautiful yellow with marbled leaves.
- ‘Marliacea Albida’: A reliable, fragrant white lily.
