Aquatic plants take up nutrients that would otherwise feed algae, shade the water and give fish cover. Lily pads can shade two-thirds of the surface, or nearly all of it if you plant them densely, and that shade holds back algae and keeps the water cooler in summer. Plants also draw nitrates and phosphates out of the water, so a well-planted pond gives algae less to feed on and often needs fewer chemical treatments. They support your filtration rather than replace it, and in a bog filter their roots give beneficial bacteria more surface to grow on.
Marginal plants such as cattails, rushes, iris and pickerelweed grow on shallow shelves and at the wet edge of the pond, with their roots in water or wet soil and their leaves above it; see shallow water plants and bog plants. Water lilies grow in deeper water, and their pads float on the surface and shade it. Oxygenating plants such as hornwort and vallisneria grow underwater, release oxygen in daylight and take up nitrates. Floating plants such as water hyacinth and water lettuce drift on the surface and take up nutrients straight from the water. A mix of all four puts plants to work at every depth, from the shallow edge to the bottom.
Water hyacinth and water lettuce are prohibited or restricted in a number of US states and can't be shipped everywhere. Check the product page for current restrictions and your state's aquatic plant rules before ordering, and never release either one into a natural waterway.
Planting Season and Timing
Hardy water lilies and marginal plants can go in from early spring through early summer. Lotus usually go in from mid-spring into early summer. Tropical lilies need water that stays at 70°F or warmer, so wait for settled summer warmth before setting them out. In colder climates, grow tropicals as annuals or overwinter them indoors. Floating and oxygenating plants can go in any time during the growing season. Not sure of your zone? Look it up with our planting zone and frost date finder.
Protecting Pond Plants from Koi
Koi eat plants, so plan for it. Pot lilies and lotus in heavy containers and cover the soil with large stones koi can't move. Plant protectors and floating plant islands keep plants out of reach. Marginal plants in shallow areas with rock barriers are generally safe, as koi tend to stay in deeper water. In a pond with a lot of koi, expect floating plants like water hyacinth to be eaten, and treat them as a snack for the fish rather than permanent decor.
Plants ship year round, weather permitting. Lotus ship in spring. Plants ship free when the plants in your order add up to $99 or more, and lotus ship separately at a flat $18. Contact us for help choosing plants for your climate.
Hardy water lilies are a good place to start. They shade the water, take up nutrients and can be potted under stones so koi can't dig them out. Marginal plants like iris and cattail are generally left alone by koi. Floating plants such as water hyacinth take up nutrients well, but koi often eat them. Water hyacinth is restricted in some states; check the product page before ordering. In a koi pond, protect oxygenating plants behind a barrier.
When is the best time to plant pond plants?
Plant hardy water lilies and marginal plants from early spring through early summer. Lotus usually go in from mid-spring into early summer. Tropical lilies need water at 70°F or warmer, so wait until summer warmth has settled in. Floating and oxygenating plants can go in any time during the growing season, as long as the water is warm enough for active growth.
How do I keep koi from eating my pond plants?
Pot plants in heavy containers and cover the soil with large stones koi can't move. Use floating plant protectors or cages around underwater plants. Some koi keepers plant a separate bog area that koi can't reach, connected to the main pond so water still circulates through it.
