Growing and Caring for Water Lilies Indoors

Water lilies are admired for their striking beauty, featuring large floating leaves and delicate, often vibrant flowers. While they flourish outdoors in ponds or sizeable water features, cultivating them inside the home can be quite challenging. Even with ideal care, getting indoor water lilies to bloom may prove difficult. If you decide to try growing them indoors, select the appropriate varieties but maintain realistic expectations.

Is It Possible to Grow Water Lilies Indoors?

For indoor cultivation, opt for hardy water lilies. Water lilies generally fall into two categories: tropical and hardy. Tropical water lilies thrive only in warm environments and boast large, colorful flowers, making them unsuitable for indoor growth. Hardy water lilies tend to be smaller, with dwarf types better suited for manageable indoor containers. Still, water lilies remain among the most demanding plants for indoor conditions.

Tips for Growing Water Lilies Indoors

Successfully growing water lilies indoors requires careful management of water temperature, water quality, and an abundance of light. Below are some important guidelines.

Light Requirements

Water lilies require as much sunlight as possible—often more than most indoor environments can provide. Ideally, they need at least four to eight hours of direct sunlight daily to grow well.

Supplemental Lighting

During winter or in spaces lacking natural light, you will need to supplement with artificial grow lights to encourage blooming. Position the lights directly over the plants and keep them on for 12 to 18 hours daily to mimic eight hours of sunlight. Finding the right type of bulb and setup may require some trial and error.

Temperature and Humidity

Maintain stable water temperatures suitable for your water lilies. While hardy water lilies do not have strict temperature demands, room temperatures around 68°F (20°C) work well. Avoid fluctuations, especially cooler nighttime temperatures. If needed, use an aquarium heater to keep the water temperature steady.

Watering Practices

When the water level drops, top it up with spring or distilled water brought to room temperature. The growing basket should be submerged at least 12 inches beneath the water surface. If using tap water, let it sit for 24 hours beforehand to allow chlorine to dissipate.

Water Circulation

Adding an air bubbler, like those used in aquariums, helps aerate the water, keeping it fresh and preventing stagnation and odors. Proper aeration also reduces the frequency of water changes.

Fertilization

Feed water lilies with liquid fertilizers or aquatic plant fertilizer tablets to promote healthy growth. Each time you add water, supplement with a small amount of fertilizer.

Pruning and Care

Remove yellowing or dead leaves promptly to maintain water quality and prevent unpleasant smells. Stagnant water odor is a common issue with indoor water lilies, though cloudy water does not harm the plants. Occasionally replacing the water is advisable.

Container and Size Considerations

Dwarf hardy water lilies can thrive in containers as small as 15 gallons, such as medium-sized fish tanks or metal tubs. The plants should be placed in net pots or baskets filled with a suitable growing medium.

Ensure the basket is compact enough to allow water circulation around it and shallow enough so its top remains submerged beneath the water surface—ideally, the water should be at least 12 inches above the basket’s top.

Growing Medium and Drainage

Though aquatic, water lilies need a substrate to grow in. Fill the net pot with small stones or gravel at the bottom to weigh it down, then add sand, perlite, or an aquatic soil mix as the growing medium.

Planting and Repotting

After preparing the pot, plant the water lily so the growing tip is just visible, while the rhizome is fully buried. Submerge the pot into the container, ensuring water flows freely around it. Repotting is usually unnecessary; once the plant outgrows its container, it’s best to start with a new one.

Transitioning Indoor Water Lilies Outdoors

Moving water lilies from indoor tanks to outdoor ponds is generally not recommended. Sudden changes in temperature and water chemistry can shock the plant, causing stress or death. If you grow water lilies indoors, it’s safer to keep them in a consistent environment rather than relocating them.