Water lilies, plants in the genus Nymphaea, are aquatic blooms that grow in ponds and water gardens. Their green lily pads spread out across the surfaces of freshwater environs and, when warm weather arrives each year, their blooms have spiky, brightly colored petals. They have floating leaves and floating blossoms—those are the showy bits, the parts that will have you oohing and aahing over your water garden once they emerge. But while these perennials appear on the surface of waters in tropical and temperate regions, their roots do need soil to survive. These eye-catching, sun-loving plants might just become your new favorite perennials to grow. Read on to learn more about water lilies, the easiest species for beginners to plant, and how to care for them in your own pond or water garden.
Plant Attributes
- Common Name: Water lily
- Botanical Name: Nymphaea spp.
- Family: Nymphaeceae
- Plant Type: Herbaceous, perennial
- Mature Size: 3 to 12 ft. wide, depending on variety; to 6 in. tall
- Sun Exposure: Full
- Soil Type: Heavy clay or loam in standing water
- Soil pH: Acidic, neutral
- Bloom Time: Summer, fall
- Flower Color: White, pink, yellow, purple, red, orange
- Hardiness Zones: Varies
- Native Area: Asia, North America
Water Lily Care
Water lilies bloom in warm weather during the late spring and summer months, and they fall dormant in autumn and winter. Some species are hardy, while others are tropical. Some bloom during the day, others at night. Many kinds are fragrant as well. The New Southern Living Garden Book describes water lilies this way: «These aquatic perennials grow with their roots in submerged soil and their long-stalked leaves floating on the surface. Floating leaves are rounded, with deep notches at one side where the leafstalk is attached. Showy flowers either float on surface or stand above it on stiff stalks.» They are typically left in their containers for planting and submerged in a natural or artificial pond. Remove yellowing leaves to maintain the health of the plant and water quality.
Light
Water lilies thrive in full sun and should be given at least six hours of direct sunlight a day. The leaves act like a sun umbrella, shading fish, keeping water temperatures cool, and reducing the growth of algae.
Soil
Heavy clay or loam soil works best for rooting plants in your pond. Don’t use potting soil or other lightweight soils, which can float to the surface. Add a thin layer of gravel over top of the soil to help keep it from clouding the water.
Water
Grow your water lily in still, standing water, but don’t plant it too deep. To get your water lilies started from tubers, The New Southern Living Garden Book recommends, «Set[ting] 6-inch-long pieces of rhizome on soil at pool bottom or in boxes and placing rhizome in a nearly horizontal position with its bud end up.» Get out your measuring stick, and ensure that the top of the soil is at least 8 inches below the surface of the water and no more than 18 inches below the surface (some larger lilies may be able to handle a 24-inch depth). Wait for the tubers to send shoots up to the surface, and watch as the leaves and blooms appear on the water.
Temperature And Humidity
Naturally, these pond dwellers have no trouble with humid summers. Tropical water lilies prefer to grow in water that is at least 70 degrees Fahrenheit.
In the South, the hardy kinds are the easiest to grow, which makes them the best choices for beginners who want to try their green thumbs at planting Nymphaea species. The American white water lily, Nymphaea odorata, can survive winters in USDA plant hardiness zones 4–11.
If you live in an area with mild winters (i.e. the Lower and Coastal South), you can plant water lilies from February to October. If you live in a region with colder winters (i.e. the Middle and Upper South), plant from April to July.
Fertilizer
For the best flowering, fertilize your plants once a month during the growing season. Press aquatic fertilizer tablets into the soil of each container.
Types Of Water Lilies
Because the hardiest water lilies are the easiest to grow, look to species such as N. odorata and selections including «Peaches and Cream», «Pink Beauty», «Sunny Pink», and «Attraction» for vibrant blooms that will be at home in Southern climates.
Pruning
Remove yellowing leaves and spent blooms from plants as they appear. Especially in a small pond or water feature, decomposing plant matter will affect water quality. Removing dead flower heads also can encourage more blooming.
Propagating Water Lilies
Water lilies are propagated by dividing the roots. This is best done in spring, when green shoots are visible on the rhizomes but haven’t fully developed into leaves. Remove the root ball from its container and lay it on a plastic sheet. Cut the rhizomes into pieces, making sure there are shoots emerging from each piece. Replant each division into a container and place in a shallow, sunny spot in the pond. After a couple of weeks, you can move the containers to a location that is deeper.
Potting And Repotting Water Lilies
Water lilies are often grown in pots to help contain their spread. Select an aquatic plant pot or plastic pot that is 14–18 inches wide. Line with burlap to keep the soil from washing out of drainage holes. Fill the pot with a heavy loam garden soil or clay soil. Set a rhizome horizontally in the pot on top of the soil with the bud end up. Add a 1-inch layer of pea gravel to anchor the plant, but do not cover the crown where leaves are emerging.
Water lilies can also be planted in fabric planting bags, which are made of a mesh material that prevents soil from washing out.
These plants should be divided and repotted every two or three years, following the instructions for propagating water lilies.
Overwintering
Hardy water lilies can remain in a pond all winter as long as the water doesn’t freeze. Here’s how to overwinter your plants:
- Remove dead or dying foliage from the plant.
- If your pond partially freezes in winter, move your water lily containers to a deeper spot that doesn’t freeze over. The plants can be moved back to the proper depth in spring.
- If you drain your pond for winter, remove any containers from the pond. Place containers in plastic bags and store in a cool spot at 40 or 50 degrees.
Tropical water lilies must be removed from the outdoors if you live in USDA zones 9 or cooler. Follow these steps to overwinter a tropical water lily:
- Wait until the plant is dormant before removing it from the pond. Remove rhizomes from the soil and wash with a strong stream of water.
- Cut any dead or dying foliage, as well as the remnants of roots and stems.
- Store rhizomes in a plastic bag filled with slightly damp peat moss or sand. Seal and store in a dark, cool room that stays above 50 degrees.
- Check on your water lilies periodically, spritzing with water if they start to dry out.
- Replant once water temperature stays above 60 degrees.
Common Pests And Plant Diseases
Fish such as koi, deer, and rodents will eat the leaves or rhizomes of water lilies. If you have fish in your pond, you can purchase floating plant protectors to create a barrier between your water lilies and aquatic animals.
How To Get Water Lilies To Bloom
If your water lilies aren’t blooming, consider these possibilities:
- Is your plant in full sun? Water lilies need ample sunshine to produce blooms.
- Did you plant your water lily too deep? Make sure the rhizome is on the surface of the soil and that the crown of the rhizome isn’t covered with gravel. Also, if your water lily is at a depth greater than 24 inches, consider moving it to a shallower spot. Some types of water lilies, like dwarf or miniature lilies, may prefer a depth of only 6 inches.
- Are your water lilies being eaten by animals? Check the container to make certain the shoots and rhizomes are not being nibbled, and install a floating plant protector if needed.
- If you have not fertilized in the last two months, aquatic fertilizer tablets can help with blooming.
- Overcrowded plants may need repotting in order to bloom.
- Are you using chemicals to control algae? Stop using these chemicals, as they will stunt the growth of pond plants.