Hardy Marginal / Bog Plants
Marginal and bog plants are traditionally planted along the margins of the pond or in moist soil. In water gardening, both marginal and bog plants are commonly referred to as marginal plants. Marginal plants often grow in the water or in moist soil. Bog plants grow only in moist soil and will often die when planted completely under water. Bog plants are indicated in the chart below with a MS in the depth column. MS stands for moist soil.
Marginal and bog plants provide the vertical touch to the water garden and make the pond look lush and attractive. The garden pond needs vertical plants to offset the horizontal surface of the water and the horizontal growth habit of the water lilies. The proper selection of marginal plants enhances the effect of the water lilies. While water lilies provide the 'pizzazz,' marginals provide the character.
Marginal plants are normally found growing in masses along the edge of ponds or streams. Masses of these plants should be used similarly in the garden pond. Massing several varieties is useful in naturalizing the garden while specimens can be planted to create dramatic effect or contrast. Specimens are particularly useful in formal gardens.
Iris are a gardener’s favorite. This is no exception with
the water iris. The elegant early flowers of spring herald the arrival
of the water lilies and provide a touch of color while you wait.
After the flowering period, the foliage of the iris is an attractive
contrast to the other marginals. Its fine textured blade complements
the coarse texture of broad leaf plants.Water iris are offered in
a full range of colors. Iris should be planted in slightly acid
Ferns add a fine textured foliage to the water garden that cannot be achieved with any other plant. They are also perfect for the shady water garden. Ferns have always been a popular perennial. Those that grow in water can add immeasurably to the water garden.
Tropical Marginal / Bog Plants
Tropical bog plants are very useful in the water garden because of their unique characteristics. Flowering tropical plants bloom continuously throughout the summer. The foliage of the tropical aquatic plants is often uniquely spectacular. The vivid colors and distinctive foliage add to the lush look often desired in the water garden. The tropical plants are sensitive to cold weather, however, and should be protected from the frost. In many cases they can be treated as household foliage plants and wintered indoors as long as they have sufficient light and moisture.
Submerged plants are essential to maintain the proper balance in the pool. They add oxygen to the water and serve as a filter by absorbing dissolved nutrients and competing with algae. Oxygenating plants are essential for pools with fish. Not only do they help establish a natural balance in the pool, they also serve as a food source, spawning area, and a hiding place for baby fish.
Oxygenating plants should be potted. They can be planted in any size container from a four inch pot to larger containers, using any good heavy soil. Do not use soiless mixes or commercial potting mixes. After planting the oxygenating plants, cover the pots with a light coating of gravel to avoid muddying the water. If large fish are present, the containers need to be covered with a protective material such as wire mesh until they become established.
Note: Place oxygenating plants in their own container, as they compete with other plants when mixed.
Floating Aquatic Plants
The floating aquatic plants listed are tropical plants and must be considered annuals in all but the most southern zones of the United States. Floating plants are very useful in the water garden helping to maintain the environmental balance. The extensive root system serves as a spawning pad and provides a place for fish to hide. The floating foliage provides shade cover which helps stabilize the water temperature. The root system helps provide oxygen. In addition, the plants compete with algae for nutrients in the water thus starving algae.
Floating Leaf Aquatics
Floating leaf aquatics are plants with foliage that float on the water surface. They are a great contrast to the larger foliage of the water lily. In addition, the flowering plants produce a proliferation of small dainty flowers in white or yellow.
Hardy Water Lilies (Nymphaea)
Hardy water lilies are plants that often are responsible for a person becoming interested in water gardening. The floating foliage, with colorful flowers interspersed throughout, creates a visual image unlike any other in the garden. Hardy water lilies are perennial, coming back year after year, to give continuous pleasure to the water gardener. They are available in white as well as all shades of red, pink, and yellow. The changeable water lilies are variations of yellow with flowers that change hue during the blooming period. In addition to being beautiful, they are useful in creating an environmentally balanced pond. The water lily pad, resting on the water surface, naturally insulates the pond. The pad reflects heat during the day and holds heat in at night thus stabilizing water temperature and assisting in algae control. It also takes nutrients out of the water which help starve algae. In order to environmentally balance a pond, 40-60 percent of the water surface should be covered with floating foliage. Water lilies are one of the plants used.
Lotus are an elegant addition to any garden pool. The leaves rise above the water surface 2 to 5 feet providing a dramatic background. Large 10 to 14 inch flowers rise above the leaves in late June and early July. The beautiful flowers and large leaves have inspired the cultures of many eastern peoples, significantly influencing their religious and daily lives. They continue to be enjoyed the world over to this day. Every garden pool should have a corner devoted to lotus.
Lotus can be used in a tub garden. When planted in tubs above ground they must be protected in winter.
Lotus are planted in large containers in soil with 6 inches of water over the tuber. Lotus require at least 6 hours of direct sunlight. Lotus tubers are extremely sensitive and must be handled with care. They can only be shipped bare root from 1 April to 1 June. After June 1 they are only sold as potted plants.
Fertilizers for Aquatic Plants
Fertilization is important in the garden pool to maintain vigorous and free flowering plants. Aquatic plants are heavy feeders during the growing season requiring a fertilizer application at least once a month. We recommend Pondtabbs, a fertilizer developed for the water gardening industry. PONDTABBS, a 10-14-8 fertilizer, is especially formulated to feed aquatic plants. At the same time, they do not release chemicals into the water which cause algae. Pondtabbs should be applied at a rate of 1 tab for each 5 quarts of soil.