Submerged Pond Plants Suitable for Ponds and Rivers in the UK
Submerged pond plants, often referred to as oxygenating plants, play a crucial role in maintaining the health and balance of aquatic ecosystems. These plants grow entirely underwater, with only their flowers occasionally rising above the surface. In the UK, submerged plants are vital for keeping ponds clean and oxygenated, providing habitat for aquatic life, and preventing the growth of algae. This essay will explore the importance of submerged pond plants and introduce several common types that are well-suited to UK ponds.
Importance of Submerged Pond Plants
Submerged plants are essential for the ecological balance of ponds. They perform photosynthesis underwater, producing oxygen that dissolves in the water, which is vital for the survival of fish and other aquatic organisms. These plants also absorb excess nutrients, such as nitrates and phosphates, which helps prevent the overgrowth of algae—a common problem in stagnant water bodies. Furthermore, submerged plants offer shelter and breeding grounds for aquatic life, including fish, invertebrates, and amphibians. By stabilising the pond’s ecosystem, these plants contribute to a clearer, healthier pond environment.
Types of Submerged Pond Plants in the UK
Hornwort (Ceratophyllum demersum)
Description: Hornwort is a popular oxygenating plant known for its feathery, dark green foliage. It floats freely in the water, although it can be anchored in the substrate if desired. Hornwort is highly effective at oxygenating the water and is tolerant of a wide range of conditions, making it ideal for UK ponds. It is evergreen, providing year-round benefits to the pond ecosystem.
Canadian Pondweed (Elodea canadensis)
Description: Canadian Pondweed is a fast-growing submerged plant that is commonly found in UK ponds and lakes. Its bright green, whorled leaves grow along a central stem, creating dense mats underwater. This plant is an excellent oxygenator and helps to clarify the water by absorbing excess nutrients.
Water Milfoil (Myriophyllum spicatum)
Description: Water Milfoil is a delicate submerged plant with fine, feathery leaves arranged in whorls around the stem. It grows well in UK ponds, providing excellent cover for aquatic life. Water Milfoil is an effective oxygenator and plays a key role in maintaining water clarity by competing with algae for nutrients. It is also used as a spawning ground by fish, making it a valuable addition to any pond.
Curled Pondweed (Potamogeton crispus)
Description: Curled Pondweed is a hardy submerged plant with distinctive, wavy-edged leaves. It is native to the UK and thrives in a variety of water conditions, including cooler temperatures. Curled Pondweed is highly effective at oxygenating the water and controlling algae growth. It typically grows during the cooler months and dies back in summer, releasing nutrients back into the pond, which can be beneficial for the ecosystem.
Spiked Water-milfoil (Myriophyllum spicatum)
Description: Spiked Water-milfoil is a submerged plant with feathery leaves that grow in a whorled pattern. It is a common plant in UK water bodies, known for its ability to thrive in a variety of conditions, including deeper water. This plant provides oxygen, shelter, and food for aquatic organisms, and its dense growth can help reduce the occurrence of algae blooms by limiting light penetration.
Submerged pond plants are indispensable for maintaining the health and vitality of UK ponds. They contribute to oxygenation, nutrient absorption, and provide essential habitat for aquatic life. By incorporating a variety of submerged plants such as Hornwort, Canadian Pondweed, and Water Milfoil, pond owners can ensure a balanced ecosystem that supports diverse wildlife while keeping the water clear and free from algae. These plants not only enhance the aesthetic appeal of ponds but also play a critical role in sustaining the delicate balance of aquatic environments in the UK.
Fennel-leaved Pondweed (Potamogeton pectinatus)
Description: Fennel-leaved Pondweed is a fine-leaved, submerged plant that is widespread across the UK. Its thin, thread-like leaves resemble fennel, hence its name. This plant is highly tolerant of varying water conditions, including brackish water, and can grow in both shallow and deep ponds. Fennel-leaved Pondweed is an excellent oxygenator and provides important habitat for aquatic invertebrates and fish.
Stonewort (Chara spp.)
Description: Stonewort, often mistaken for a type of algae, is a submerged plant that grows in clear, nutrient-poor waters. It has a rough texture and gives off a distinctive scent when crushed. Stonewort is beneficial for maintaining water clarity as it thrives in clean water and absorbs nutrients that might otherwise feed algae. It’s commonly found in UK ponds and can be an indicator of good water quality.
Bladderwort (Utricularia vulgaris)
Description: Bladderwort is a fascinating submerged plant that is carnivorous, trapping small aquatic organisms in tiny bladder-like structures. It has delicate, feathery leaves and produces small yellow flowers that emerge above the water surface. Bladderwort is found in various regions of the UK, particularly in nutrient-poor ponds. It plays a unique role in pond ecosystems by controlling populations of small aquatic organisms while also oxygenating the water.
Eelgrass (Vallisneria spp.)
Description: Eelgrass, also known as tape grass, has long, ribbon-like leaves that grow from the base of the plant and can reach several feet in length. It is an excellent oxygenator and is often used in larger ponds and lakes. Eelgrass is well-suited to UK ponds, particularly those with softer water, and provides valuable cover for fish and invertebrates. It’s also effective at stabilising pond substrates and reducing sediment resuspension.
Water Crowfoot (Ranunculus aquatilis)
Description: Water Crowfoot is a versatile plant that can either be submerged or float on the surface of the water. It has finely divided leaves that provide good cover for aquatic life and produces small, white flowers that bloom above the water in spring and summer. Water Crowfoot is native to the UK and thrives in a wide range of water conditions, making it a valuable plant for both ornamental and natural ponds.
Whorled Watermilfoil (Myriophyllum verticillatum)
Description: Whorled Watermilfoil is another species of milfoil commonly found in UK ponds. It has similar characteristics to other milfoil species, with fine, feathery leaves arranged in whorls along the stem. This plant is particularly good for oxygenation and providing habitat for pond life. It can tolerate a range of water conditions, making it a resilient choice for UK ponds.
Sago Pondweed (Stuckenia pectinata)
Description: Sago Pondweed is a robust, submerged plant with long, slender leaves. It is common in UK waters, especially in areas with high nutrient levels. Sago Pondweed is highly effective at oxygenating the water and provides an important food source for waterfowl and aquatic invertebrates. It can thrive in both fresh and brackish water, making it versatile for different types of ponds.
Water Violet (Hottonia palustris)
Water Violet is a beautiful submerged plant with finely divided leaves that form dense, bushy underwater growth. It produces attractive, pale lilac flowers that rise above the water surface in late spring. Water Violet is native to the UK and prefers clear, still waters. It is an excellent oxygenator and is particularly valued for its ornamental appeal in garden ponds.
Brooklime (Veronica beccabunga)
Description: Brooklime is a native UK plant that can grow submerged, with its creeping stems often rooting along the pond bottom. It has bright green leaves and produces small blue flowers. Brooklime is commonly found in shallow water and along pond edges, where it provides excellent cover for aquatic life. It’s a resilient plant that can tolerate a range of conditions and helps to oxygenate the water.
Fanwort (Cabomba caroliniana)
Description: Fanwort is a popular submerged plant known for its delicate, fan-shaped leaves that create a lacy appearance underwater. While not native to the UK, it can thrive in UK ponds with the right conditions. Fanwort is an excellent oxygenator and provides good cover for small fish and invertebrates. However, it can be sensitive to cold, so it may require some protection in harsh winters.
Hairgrass (Eleocharis acicularis)
Description: Hairgrass, or Dwarf Hairgrass, is a fine, grass-like plant that grows submerged in shallow water. It is often used in aquascaping but can also thrive in ponds. Hairgrass forms dense mats that help stabilise the pond substrate and provide habitat for small aquatic organisms. It is tolerant of a range of water conditions and can survive in the UK climate.
Water Purslane (Lythrum portula)
Description: Water Purslane is a low-growing, creeping plant that can grow submerged in shallow water or along pond edges. It has small, rounded leaves and produces tiny pinkish flowers. Water Purslane is native to the UK and can tolerate a variety of water conditions, making it a versatile choice for natural and ornamental ponds. It contributes to oxygenation and helps control algae growth by competing for nutrients
Pondweed (Potamogeton natans)
Description: This species of Pondweed is a native UK plant that can grow submerged, though its broad, floating leaves are often visible on the water’s surface. It thrives in a range of water conditions, including deeper ponds. Pondweed provides excellent cover for aquatic life and helps oxygenate the water, making it a beneficial addition to both natural and garden ponds.
Zannichellia (Zannichellia palustris)
Description: Also known as Horned Pondweed, Zannichellia is a submerged plant that grows in shallow waters across the UK. It has slender, thread-like leaves and is well-suited to ponds with fluctuating water levels. This plant is an effective oxygenator and provides food and habitat for aquatic invertebrates and waterfowl. Its adaptability to different water conditions makes it a reliable choice for UK ponds.
Fool’s Watercress (Apium nodiflorum)
Description: Fool’s Watercress is a native UK plant that can grow both submerged and partially emerged. It has bright green, compound leaves and small white flowers. This plant is commonly found in streams and pond edges, where it provides shelter for aquatic life and contributes to oxygenation. It is a robust plant that can thrive in a variety of water conditions.
Pennywort (Hydrocotyle vulgaris)
Description: Pennywort is a creeping plant that can grow submerged in shallow water. It has round, coin-shaped leaves and is often found along the edges of ponds and wetlands in the UK. Pennywort is valued for its ability to stabilise the pond margins and provide habitat for aquatic organisms. It is a hardy plant that can tolerate cooler temperatures, making it suitable for UK ponds.
Water Buttercup (Ranunculus aquatilis)
Description: Water Buttercup, also known as Water Crowfoot, is a submerged plant with finely divided leaves that create a soft, feathery appearance underwater. It produces small, white flowers that bloom above the water surface in spring and summer. This plant is native to the UK and is commonly found in clear, shallow waters. It is an excellent oxygenator and supports a diverse range of aquatic life.
Conclusion
The variety of submerged pond plants available for UK ponds ensures that pond owners can create a diverse and thriving aquatic environment. From the creeping Brooklime and Pennywort to the more delicate Fanwort and Water Buttercup, each plant offers unique benefits in terms of oxygenation, habitat provision, and water quality maintenance. By selecting a mix of these submerged plants, UK pond enthusiasts can enhance the ecological health of their ponds, supporting a wide range of aquatic life while maintaining a clear and balanced water environment throughout the year