Detailed Explanation of Key Cultivation Techniques for Aquatic Flowers
Aquatic flowers are an important component of ornamental plants in gardens and courtyard waterscapes. They broadly refer to ornamental plants that grow in water or marshes. What clearly sets them apart from other flowers is that their demand for and dependence on water far exceeds that of other categories, which also gives rise to their unique habits. Let us now take a look at the cultivation techniques for aquatic flowers!
Cultivation Value of Aquatic Flowers
Aquatic flowers are important materials for laying out waterscape gardens. A single lake or pond may use multiple species, or just one, forming scenic areas and viewpoints of unique charm together with garden structures such as pavilions, waterside houses, halls, and guesthouses. Large lakes can be planted with submerged species such as bittercress, lakesides and marshes can be planted with marsh plants, and medium and small ponds are suitable for medium and small varieties of lotus or water lilies, water hyacinths, and the like. For ponds with piled mountains and stacked rocks, cattails and sweet flag are suitable for planting at the pond corners and along the banks, while aquatic irises, rushes, and similar plants are suitable for planting in the rock crevices of rockeries and waterfalls or in stone gaps beside streams. However, the quantity of aquatic flowers used for waterscape arrangement should not be too great; they should be arranged with a pleasing balance of density and sparseness, with beautiful water and abundant flowers, and the plants should not completely cover the water surface.
Common Types of Aquatic Flowers
1. Emergent plants: lotus, bowl lotus, reed, cattail, wild rice stem, water celery, giant reed, water bamboo, sweet flag, pampas grass, water chestnut, etc.
2. Floating-leaved plants: water lily, water hyacinth, duckweed, spatterdock, Nymphoides, arrowhead, water caltrop, euryale, small floating lotus, etc., mainly plants of the Nymphaeaceae family.
3. Submerged plants: bitterweed, black algae, hornwort, Myriophyllum, lantern algae, pondweed, prickly algae, bladderwort, etc., mainly aquatic grasses.
4. Emergent herbaceous plants: canna, pickerelweed, purple loosestrife, Thalia, aquatic iris, red knotweed, Pennisetum, cattail grass, Alisma, and other plants suitable for growing at the water's edge.
Propagation Techniques for Aquatic Flowers
1. Seed propagation: The sowing method for aquatic flowers is to sow the seeds in a pot with culture soil, cover with sand or soil, and then immerse the pot in water. The immersion process should be carried out gradually, from shallow to deep. The germination speed of seeds varies by species. Cold-hardy species germinate more slowly and need 3 months to 1 year, while non-cold-hardy species germinate faster and can germinate about 10 days after sowing. Sowing can be done indoors or outdoors. Indoor conditions are easy to control, while outdoor water temperature is difficult to control, which often affects the germination rate.
2. Division propagation: Most aquatic flowers grow in clumps or have underground rhizomes and can be directly divided or have their rhizomes cut into several sections for planting. When dividing rhizomes, note that each section must have a terminal bud and tail roots, otherwise it will be difficult to form a plant. Division is generally carried out in spring and autumn; some non-cold-hardy ones can be done in late spring and early summer.
Cultivation Techniques for Aquatic Flowers
1. Sunlight: Most aquatic plants need ample sunlight, especially during the growing period (that is, between April and October each year). If sunlight is insufficient, they will become leggy, with small and thin leaves, and will fail to bloom.
2. Soil: Apart from floating plants, which do not need bottom soil, planting other types of aquatic plants requires field soil, pond mud, and other organic clayey soil as the bottom soil. A layer of coarse sand with a diameter of 1 to 2 cm should be spread on the surface, which can prevent the water from becoming turbid due to watering or vibration.
3. Fertilizing: Use oil cake and bone meal jade fertilizer as base fertilizer. About four or five jade fertilizer pieces placed in the corners of the container is enough. Waterside plants do not need base fertilizer. For topdressing, use chemical fertilizer instead of organic fertilizer to avoid polluting the water quality, and the amount used should be ten times more diluted than for ordinary plants.
4. Water level: Aquatic plants have different requirements for water depth according to their growth habits. Floating plants are the simplest and only need enough water depth to float. For submerged plants, the water must be higher than the plants so that the stems and leaves can extend naturally. Waterside plants should keep the soil moist and slightly waterlogged. Because the stems and leaves of emergent plants extend above the water surface, a water depth of about 50 cm to 1 m must be maintained. Floating-leaved plants are more troublesome; the water level must be adjusted according to the length of the stems and stalks so that the leaves float on the water surface in a natural state.
5. Thinning: If various types of aquatic plants are planted together in the same pond, fast-propagating species must be thinned regularly to prevent them from covering the water surface and affecting the growth of water lilies or other submerged plants. When floating-leaved plants become too large and their leaves cover one another, division must also be carried out.
6. Changing water: To avoid mosquito breeding or deterioration of water quality, water must be changed when the water becomes turbid, and in summer the frequency of water changes must be increased.