Plants for a small pond provide beauty and function to a water garden. Choose plants with ornamental value, but also consider the practical functions of water plants, including oxygenation, algae reduction and nitrogen uptake. Plan carefully to maintain a balance of plant types and purchase specimens from reputable aquatic plant providers. Limit pond plants to no more than two-thirds of the water's surface, advises Colorado State University Cooperative Extension. Consult a county extension or Parks and Wildlife office for information regarding aggressive, restricted aquatic plants.
Floating plants add a decorative touch to the pond's surface and shade the water, reducing algae growth. Giant velvet leaf (Salvinia longifolia) is a small tropical floating fern with round, pale green, fuzzy leaves. Water lettuce (Pistia stratiotes) has velvet-green leaves with rosette foliage appearing like a head of lettuce.
Submerged water plants oxygenate ponds and maintain a healthy ecosystem. Restricted plants vary by location. The roots of submerged plants anchor the plants and may be potted in gravel containers inside the pond. Submerged plants include: ribbon-like wild celery (Vallisneria spp.), fan-like fanwort (Cabomba canadensis) and parrot feather (Myriophyllum aquaticum).
Surface plants root in the pond soil (or in pots) and have long stems with floating leaves. Surface plants include: lotus (available in dwarf varieties for small ponds), blue flag iris (Iris versicolor) and water blue bells (Ruellia brittoniana). Dwarf varieties of water lilies are another choice, consisting of hardy and tropical types. Hardy water lilies include some cultivars with blooms that change color over time. Tropical water lilies are divided into two groups: day bloomers and night bloomers.
Plants surrounding the pond edge are also called shoreline, marginal or bog plants. Plant bog plants in shallow water near the pond edge or in moist soil surrounding the pond. Surrounding pond plants include species such as Lobelia, dwarf papyrus (Cyperus isocladus), corkscrew rush (Juncus effusus), colorful water cannas and arrowhead (Sagittaria species).