Natural swimming pools are increasingly becoming a popular choice for those seeking an eco-friendly alternative to traditional, chemically-treated pools. These pools offer a refreshing, chemical-free swimming experience and support a more sustainable lifestyle. However, the success of a natural pool heavily relies on the selection of appropriate plants, which play a crucial role in filtering and purifying the water.
Plants in a natural swimming pool serve distinct purposes. Oxygenating plants help keep the water clear and healthy, while marginal plants stabilize the pool’s edges and attract beneficial wildlife. Selecting the right mix of plants ensures that your pool remains clean, balanced, and low-maintenance throughout the year.
To help you create a harmonious and inviting natural pool, we consulted with gardening and pool experts to identify some of the best plant options.
Best Plants for a Natural Swimming Pool
When choosing plants for a natural swimming pool, it’s essential to include a mix of submerged, floating, and emergent varieties to establish a balanced ecosystem. Here are eight of the best plants to consider:
1. Vallisneria
Growing Information: Submerged plants are vital for maintaining the health and vibrancy of natural swimming pools. Peggy Wiles, managing partner at California Natural Pools, recommends Valisneria americana, also known as Corkscrew Vallisneria. This plant is an excellent oxygenator and nutrient consumer, effectively curbing algae growth through allelopathy (the inhibition of one plant’s growth by another). With its spiral-shaped leaves, Corkscrew Vallisneria not only adds visual appeal but also supports a thriving ecosystem by oxygenating the water and controlling algae.
2. Water Lilies
Growing Information: Water lilies are iconic and essential for natural pools. Their large leaves cover wide surface areas, limiting sunlight and preventing algae blooms. Jennifer Cassels, president of The Blissful Place, highlights that water lilies also offer shelter for aquatic life, enhancing biodiversity. These plants grow best in stagnant or slow-moving water and require minimal care once established. Plant them in containers submerged on the pool floor for easy transfers and depth adjustments.
3. Hornwort
Growing Information: Hornwort is a submerged plant valued for its vigorous growth and low maintenance needs. Jennifer Cassels notes that hornwort acts as a natural filter, absorbing excess nutrients that could otherwise fuel algae growth. Its feather-like foliage provides safe zones for smaller aquatic creatures, contributing to the overall health of the pool ecosystem. As a rootless plant, hornwort floats freely, adjusting to various depths. To maintain water quality, regularly thin out overgrown sections.
4. Yellow Flag Iris
Growing Information: Yellow flag iris is an excellent choice for stabilizing the edges of your natural pool. With vibrant yellow blooms and a strong root system, it prevents soil erosion and keeps the pool banks intact. Jennifer Cassels advises planting irises in shallow areas with consistently moist soil or along the water’s edge, ensuring they receive full sunlight. Regularly divide and replant rhizomes to encourage growth and prevent overcrowding, as yellow flag iris can be invasive.
5. Cattails
Growing Information: Cattails are known as “the workhorses of the natural pool world,” according to arborist and landscape gardener David Miller. These plants thrive in shallow water, filter out impurities, and create a dynamic, natural look with their tall, reed-like appearance. Cattails are essential for maintaining water quality by trapping sediments and pollutants, while also providing habitat for birds and other wildlife.
6. Pickerelweed
Growing Information: Pickerelweed, a tall, emergent plant with heart-shaped leaves and vibrant blue flowers, is excellent for absorbing nutrients from water and improving clarity. David Miller praises pickerelweed for its beauty and its ability to support beneficial insects. However, pickerelweed can be invasive in some areas, so it’s important to check local guidelines before adding it to your pool.
7. Water Mint
Growing Information: Water mint is both beautiful and practical, forming a lush green border around the water’s edge. David Miller notes that water mint competes naturally against algae, helping to keep the pool clear. Its minty scent also enhances the overall experience of the pool area.
8. Marsh Marigold
Growing Information: Marsh marigold is one of the best oxygenating plants for ponds. With bright yellow blooms in early spring, it thrives in shallow water zones or along the pool’s edge. The shallow root system helps stabilize the pool’s edges, reducing erosion. Additionally, its vibrant flowers attract pollinators, enhancing the ecological diversity of the pool area.
Key Considerations When Selecting Plants for Natural Pools
Choosing the right plants for your natural swimming pool requires careful consideration of several factors:
Climate Adaptability: Ensure that the plants you select are suited to your climate zone. For warmer climates, consider plants like water hyacinth or taro. In cooler climates, opt for hardy plants like marsh marigold or sweet flag.
Pool Position and Depth: Different plants thrive in various water depths and light conditions. Sun-loving plants like water lilies should be placed in well-lit areas, while shade-tolerant plants like marsh marigold are better suited to partially shaded spots. Separate your primary aquatic plant zone from the swimming zone to avoid plant damage.
Watering Needs: Match plants to the water conditions in your pool. Some plants, like water lilies, thrive when submerged, while others prefer moist soil along the pool’s edge. In areas with limited water, opt for low-water-use plants like sweet flag or creeping jenny to conserve resources and reduce maintenance.
Maintenance Needs: Native species are ideal for beginners as they require less care and are more resistant to pests and diseases. Plant in spring or early summer, use aquatic soil or gravel, and avoid overcrowding. Regularly prune dead leaves, remove debris, and monitor nutrient levels to maintain a healthy pool ecosystem.
Aesthetic Appeal: Consider the visual impact of your plant choices. Select a mix of textures, colors, and forms that complement the overall design of your pool area. Incorporate plants with year-round interest, such as cattails and water lilies, and create depth with varying heights like pickerelweed and water mint.
By carefully selecting and maintaining the right plants, you can create a beautiful, eco-friendly natural swimming pool that is both inviting and sustainable.