Marginal Pond Plants
The marginal plant group is the largest aquatic plant group by far, containing both hardy and tropical plants. Most of them are true perennials and come back year after year, like your favorite Daylily or Black-Eyed Susan.
Marginal plants serve many functions, such as adding beauty and providing valuable filtration. They are called “marginals” because they typically grow around the edges or “margins” of a pond or lake.
Marginal plants typically thrive in wet soil of standing water that covers the crown or base of the plant by as little as two inches and up to as much as six inches.
Here are some fun facts about a few popular marginals:
Horsetail (Equisetum) was a major part of the vegetation during prehistoric times, as it is said to have been the size of trees, making up huge horsetail forests. The species we see today growing in our ponds are much smaller.
The trailing stems of Creeping Jenny (Lysimachia nummularia ‘Aurea’) have round, chartreuse leaves that make an excellent ground cover for the edge of the pond or container water garden. The color of this plant is a great accent to an assortment of other foliage or flower colors, but looks especially interesting next to deep purple.
Dwarf Variegated Sweetflag
Also known as golden Japanese sweetflag (Acorus gramineus ‘Ogon’), this plant is ideal for container water gardens and water gardens alike. It’s extremely flexible, as it can be grown with its toes in the water or partially submerged. The beautiful foliage is light green and highlighted with bright yellow stripes, remaining beautiful all season and sometimes through the winter. An all-around great plant that adds a bright, cheerful spot to any water feature!
Many water gardeners enjoy the elegant splendor of the aquatic iris, which is among the first plants to bloom in the spring. Aquatic irises comprise such a large and diverse group – there are literally hundreds, if not thousands of cultivated and natural hybrids. The blue flag iris is a native plant that can grow up to four feet tall! A wetland lover, the blue flag’s large flowers are breathtaking, ranging in shades from pale blue to purple.
Dramatic and elegant, Taro (Colocasia spp.) enjoy hot, humid weather and love to be fertilized. Heart-shaped leaves on stalks up to 48” tall make Taro an ideal choice for water gardens, container gardens, and bog gardens. Ranging in color from burgundy-black to green velvet, this plant offers a striking backdrop for shorter aquatics. Add this specimen to your pond for architectural interest.
Countless more marginal plants are available to spruce up your pond and you’re sure to find favorites that aren’t listed here. Just be sure to follow the grower’s instructions for the plants you select and you’ll be well on your way to naturalizing your water garden.