I've dabbled in growing Nymphaea indoors, and it's a rewarding but slightly challenging endeavor. Choosing the right container is essential; a wide, shallow pot or water-tight container is ideal, as water lilies need room for their leaves to spread across the surface. It's also important to make sure the container is deep enough to cover the roots by at least 10 to 12 inches.
For lighting, since water lilies are sun-loving plants, providing them with ample bright, indirect sunlight is crucial. If natural light is insufficient, consider using a full-spectrum grow light to mimic the daylight they would receive outdoors. Place the light close enough to provide adequate coverage but far enough to avoid overheating the leaves.
The water temperature should be kept consistent, ideally between 70-80°F. A small aquarium heater might be necessary if your indoor environment tends to be on the cooler side. Regularly check the water quality, as stagnant water can become a breeding ground for mold and unwanted organisms. Including a small water pump or bubbler can help circulate the water and oxygenate it.
Maintenance includes removing any dead or decaying leaves regularly to prevent them from fouling the water. Keep an eye out for pests like aphids, which can sometimes be a nuisance indoors. Providing a small, balanced fertilizer specifically designed for water plants can support their growth, but use it sparingly to avoid algae bloom.
Starting with a hardy variety like Nymphaea 'Pygmaea Helvola' might be easier, as they are more adaptable and smaller, which suits indoor settings well.
If you want to dive deeper into cultivating water lilies, books dedicated to aquatic plants or resources from botanical gardens can offer detailed guidance. Enjoy experimenting with this beautiful addition to your indoor collection!