Cattails (Typha) are perennial aquatic plants known as emergent macrophytes, meaning they grow in water but their foliage extends above the surface, typically along shallow margins. In moderation, they offer several ecological benefits. They provide natural filtration by absorbing excess nutrients like nitrogen and phosphorus, which improves water quality and limits algae growth. Their dense, fibrous root systems stabilize the pond’s edge, protecting against shoreline erosion. The tall stalks and flowering heads also create valuable habitat and cover for wildlife, including nesting birds and beneficial insects.
Preparing the Pond Environment and Plant Selection
The success of planting cattails hinges on selecting the proper location and the right species for the water garden’s size. Cattails thrive in the littoral zone—the shallow, near-shore area of the pond. Most varieties perform best when the base is submerged in 6 to 12 inches of water, though some broadleaf species tolerate up to 24 inches. Cattails require a location that receives full sun for at least six to eight hours daily to ensure vigorous growth.
Choosing the right species is the most important decision for avoiding aggressive overgrowth. The common broadleaf (Typha latifolia) and narrowleaf (Typha angustifolia) cattails spread rapidly through extensive underground rhizomes and wind-blown seeds, making them highly invasive in smaller ponds. For small or ornamental water features, a dwarf cultivar such as Typha minima is more manageable. This smaller variety typically grows only 18 to 24 inches tall and is significantly less aggressive, making it ideal for container planting. Plants can be sourced as bare root rhizomes or potted specimens.
Detailed Planting Procedures
The recommended method for planting cattails in a managed pond is containment, which severely limits rhizome spread. This involves planting them into heavy, solid containers that lack drainage holes, such as plastic tubs or specialized aquatic baskets. These containers must be sturdy, as the extensive root systems can easily break through flimsy materials. The planting medium should be heavy clay or loam soil, which is distinct from lightweight commercial potting soils that float and release excess nutrients.
After selecting the container, fill it partially with heavy soil. Position the rhizome horizontally or upright with the crown just above the soil line, then fill the remaining space with soil. To prevent the soil from clouding the water when submerged, cover the top layer with one to two inches of pea gravel or crushed stone. Gently lower the container onto a shelf or ledge in the designated shallow water area. The water depth should maintain the plant’s crown submerged between 4 and 12 inches, depending on the species.
For large, naturalized ponds or constructed wetlands where control is less of a concern, direct planting into the mud bottom is an option. This involves securing the rhizomes directly into the soft substrate near the shoreline. While this method allows for a more natural appearance and maximum filtration, it requires frequent, aggressive management to prevent colonization of the entire shallow perimeter. Spring is the ideal time to establish new cattail plants, allowing them the full growing season to establish root systems before winter.
Post-Planting Care and Spread Management
Managing aggressive cattail growth is an ongoing process necessary to prevent them from overtaking the pond. The primary mechanism of spread is the rhizome, the thick underground stem that produces new shoots. For container-planted cattails, the most effective control is physically removing the container every two to three years and dividing the root mass. This division involves using a sharp knife to cut the rhizomes into smaller sections, which can be replanted or discarded, rejuvenating the plant and controlling its size.
For cattails planted directly into the pond bottom, mechanical removal, which involves physically digging up the rhizomes, is the typical approach. Another effective control method is cutting the stems below the waterline late in summer or early fall when plants transport resources to their roots. Cutting the stalks below the surface causes the submerged portion to flood with water, effectively drowning the rhizome by depriving it of atmospheric oxygen. Regular maintenance involves cutting back dead or brown stalks, usually in late fall or early spring, though it is important to cut them above the water level if they are not being removed for control.