How to Grow and Care for Water Lilies
Water lilies add a touch of magic to freshwater ponds or containers. Some of these exotic-looking beauties bloom during the day, while others reveal their cup or star-shaped flowers at night.
Some plants don’t grow in regular potting soil. Lovely water lilies grow from tubers, or rhizomes, in freshwater ponds or pots filled with aquatic potting mix and submerged in half-barrels, stock tanks or tubs. Lily pads, which are their leaves, float on the surface. These members of the Nymphaeaceae family come from temperate and tropical regions, where fish and other wildlife use them for food, but there are lots of ornamental types.
Water lily flowers come in shades of yellow, pink, red, orange, blue, purple or white, and some are fragrant. Tropical types that are hardy in zones 10 and 11 need water temperatures at or above 70 degrees F. Perennials are hardy in zones 4 to 11.
Tropicals are day- or night-bloomers, while hardy water lilies open their flowers during the day and close them at night. Most water lilies bloom from May to September.
How to Plant Water Lilies
Water lilies (sometimes spelled waterlilies) need still or slow-moving water. Grow them in plastic pots, plastic mesh pots or pots made for aquatic plants that measure about 18 inches in diameter and 10 inches deep. Line mesh pots with newspaper or burlap so the aquatic mix won't come out. If you use a wooden half-barrel to create a water lily pond, line it with heavy plastic to protect your plants from any residue from its previous contents.
Fill your container half-full of aquatic planting mix. If you prefer, use heavy clay dug from your garden. Put the tuber toward one side of the container at a 45-degree angle. Point the growing tip up and toward the middle of the container. Cover the plant with more mix or clay but don’t bury the crown or growing tip. Insert an aquatic plant fertilizer tablet as directed on the product's label.
Add an inch of pea gravel to the top of the pot and water it. Slowly lower it into your pond or a larger container of water so the top of the pot is 18 to 24 inches below the surface. If it sits too low, put some rocks underneath it to raise it. If you’re using a premade pond, place the pot on a shallow, built-in planting ledge.
Don’t crowd the body of water with the lilies or other aquatic plants. Leave a quarter to a third or more of the water's surface open.
Never put water lilies directly into a river, natural pond or lake since some are invasive and will choke out native species. When you divide them, give away, replant or discard your extras.
After the water lily flowers fade, cut off the stalks as far down as possible to encourage more blooms.
How to Grow Water Lilies
Most water lilies need at least six hours of direct sun each day, although some will bloom with four.
Feed water lilies with aquatic fertilizer tablets at planting time and again as indicated on your product.
In the spring, lift potted lilies and repot them in fresh aquatic mix or clay. If the roots are too dense to insert new fertilizer tablets, divide the plants.
Caring for Water Lilies in Winter
Hardy water lilies can overwinter outside if the rhizomes don’t freeze. If your water will freeze, or you're going to drain your water, lift the rhizomes and store them indoors in plastic bags to keep them moist. If you prefer, take the rhizomes out of their pots, brush them off and store them in sawdust or peat moss in a location that stays 40-50 degrees F. Repot them next spring.
Bring tropical water lilies indoors, still in their pots, and store them in plastic bags. Keep them in a location that stays around 50 degrees F and check regularly to be sure they stay moist. Take them back outside when warm weather returns.
Water Lily Pests and Diseases
Aphids can make water lily leaves turn yellow and curl. Rinse them off the lily pads or submerge the leaves for a couple of days to drown these pests.
Pick off small water lily beetles that make holes in the leaves or rinse them off.
Put mosquito dunks in the water to control midges that make wavy cuts in leaves.
Many hybrids are disease-resistant, but if your leaves turn yellow and separate from the crown, the tuber may have crown rot. Take it out of the water, cut off any infected parts and rinse the rest of it under running water. This disease is contagious, so quarantine the tuber in a separate container until there are no new signs of disease. Discard badly rotting tubers.
Leaf spot makes dark patches or spots on leaves until they turn brown and die. Remove the infected leaves or discard the tuber if more than half of it is damaged.
How to Propagate a Water Lily
When new growth begins in spring, take your water lily out of the water and divide the rhizome into 4-inch sections. Each one should have a growing tip and some thin feeding roots. Cut off the long, thick roots to 6 inches, measuring from the rhizome. Repot the sections.
Types of Water Lilies to Grow
Amazonian lilies (Victoria amazonica) are the biggest water lilies in the world, growing up to 10 feet wide. Their giant lily pads are round and turned up on the edges. Hardy in zones 10 and 11, these tropicals have red leaves with sharp spines that deter hungry fish. Giant water lily flowers are fragrant and last about two days. They usually open white and change to pink or reddish.
‘Star of Siam’ Nymphaea is a tropical with blue, star-shaped blooms and white stamens with violet tips.
‘Helvola’ is a miniature hardy lily. Its fragrant yellow blooms stand out against dark green leaves with purple speckles.
‘Paul Hariot’ has cup-shaped flowers that open to creamy yellow before turning light pink.
‘Pink Grapefruit’ has green lily pads with reddish speckles. The large flowers of this hardy lily are peach-pink.
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This Egyptian lotus has fragrant pink petals that age to deep rose. Large, round leaves with a silvery sheen float on the water.
‘Little Sue’ is a perennial with blooms that change from light to dark peach. It's great for small ponds or tubs.
Nymphaea caerulea, or Egyptian Blue Water Lily, is a day-blooming hardy plant with light blue flowers and gold stamens. In nature, it’s endangered.
Lotus are plants that also bloom from rhizomes and grow in ponds, but they’re not the same as water lilies. They have thin, papery leaves and flowers, while water lilies have thick, waxy foliage.