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Water hyacinths (Eichhornia crassipes) are one of the most beautiful water garden plants, but they can be harmful if they get too wet. Flower stalks that grow about six inches (15 cm. In the spring, flowers rise from the centers of the rosettes above the leaves. By the end of spring, each plant has up to twenty beautiful purple flowers. The flowers last until fall and make striking cut flowers.
Water hyacinths (Eichhornia crassipes) are popular floating plants for ponds and water gardens. With their lush green leaves and stunning purple flowers, they add beauty to water features. But getting them to bloom can be tricky. Here’s what you need to know about when and how to get water hyacinths to flower.
Ideal Conditions for Blooming
Water hyacinths thrive in warm weather and full sun. They bloom most prolifically during the hottest summer months. Cooler temperatures and shorter days in spring and fall limit flowering. In frost-free climates like Southern Florida and Southern California, water hyacinths may bloom year-round if given sufficient sunlight.
But even in the peak of summer, shady conditions can prevent water hyacinths from blooming. They need at least 6 hours of direct sunlight daily for best results Filtered sunlight through tree leaves or shadows cast by buildings usually isn’t enough
Stagnant, nutrient-rich water also promotes flowering. Gentle water movement from fountains and waterfalls helps somewhat. But vigorous filtration and water changes can inhibit blooms by removing the nutrients these heavy feeders need.
Typical Blooming Season
In most temperate climates water hyacinths bloom primarily from mid-summer through early fall. Peak flowering typically occurs from July through September. A few flowers may appear in late spring, but cool temperatures limit proliferation.
Once nighttime temperatures drop below 60°F in fall, blooming sharp declines. A few flowers may linger into October if daytime temperatures remain warm. But frost quickly kills back water hyacinths, eliminating any remaining blooms.
In warmer climates across the Southern U.S., water hyacinths often begin blooming prolifically in May or June. Flowers continue through the summer into the fall. The onset of cooler weather in November or December brings the season to an end.
Encouraging Water Hyacinths to Bloom
If your water hyacinths aren’t blooming well, there are a few tricks to promote better flowering:
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Grow them in full sun – at least 6 hours of direct sunlight per day. Morning sun is ideal.
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Allow the plants to become root-bound. Crowding triggers blooming.
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Keep the water warm – ideally 75-85°F. Heat accelerates growth and flowering.
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Avoid vigorous water circulation or frequent water changes. Stagnant, nutrient-rich water prompts blooms.
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Apply a diluted fertilizer every 2-4 weeks. Nitrogen and phosphorus fuel flowering.
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Don’t over-trim or divide the plants. Mature, uninterrupted growth results in more flowers.
With the right conditions, your water hyacinths should reward you with an abundance of gorgeous blooms to enjoy from mid-summer into fall. Just be patient through the cooler seasons until warmth returns.
Regional Blooming Seasons
Water hyacinths bloom at slightly different times across North America depending on local climate conditions:
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Southern Florida – Flowers from May through November, with peak blooms June-September
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Gulf Coast – Blooms from June through October, peaking in July and August
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Southern California – Blooms April through November, with most flowers June-September
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Southwest – Typical flowering months are July through September
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Mid-Atlantic – Blooms from July to September in most areas
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Midwest – Flowers primarily August and September
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Northeast – Mostly blooms August into early October
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Pacific Northwest – Very limited flowering typically only in August
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Canada – Seldom bloom; may see a few flowers in late August
So adjust your expectations based on your local climate. Given the right conditions, water hyacinths will flower prolifically during the hottest months wherever you live.
Overwintering for Early Season Blooms
In cold winter regions, starting water hyacinths early indoors allows them to bloom weeks earlier in spring. Around March, place dormant plants in a sunny window or under grow lights. Pot them in shallow water, keeping the crowns above water.
Once new growth appears, move them to an outdoor tub with warm water on a sunny patio or deck. Introduce the water hyacinths to the pond after nighttime temperatures stay consistently above 50°F. With this head start, plants may begin blooming by late May or early June.
Enjoying the Spectacular Blooms
The brilliant purple flowers of water hyacinths add striking late-season color to ponds and water features. Get your plants blooming at their peak by providing plenty of warmth, sunlight and nutrients. Position containers where you can best appreciate the beautiful blooms. And trim off spent flower spikes to encourage more blossoms. With proper care, you’ll enjoy a bountiful display.
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How to Grow Water Hyacinth
Growing water hyacinth plants is easy. Once they’re established, they don’t need any special care, but they do need to be thinned every so often to keep them from suffocating everything else in the pond. Under perfect conditions, a colony of water hyacinths can double its size every 8 to 12 days. Water hyacinths need full sun and hot summer temperatures. Introduce them to the garden by scattering bunches of plants over the surface of the water. They quickly take hold and begin to grow. Thin the plants when they cover more than 60 percent of the water surface. Water hyacinth plants survive winters in U. S. Department of Agriculture plant hardiness zones 8 through 11. They do best as annuals in places where cold winters kill them back every year. In warmer areas, these plants do become invasive. You can overwinter them indoors in a sunny spot, but they are inexpensive to replace each year. Most gardeners dont find them worth the trouble to keep over winter.
Container Grown Water Hyacinths
A half barrel is an ideal container for a water hyacinth. For garden ponds, the plants need full sun. In pots, however, they do best with shade from mid- to late-afternoon. Cover the inside of the barrel with a strong trash bag, and then fill the bottom of the container with soil. Don’t use store-bought potting soil; it has chemicals and fertilizers in it that could hurt the plant and make algae grow faster. Commercial soils also contain perlite and vermiculite, which floats to the top of the container. Cover the soil with a thin layer of sand. City water is usually treated with chlorine or chloramine, which is harmful to plants. Garden stores sell things that make water safe for plants by getting rid of chlorine and chloramine. The small amounts of water you use to fill up the container during the season don’t need to be treated. Putting one end of a nylon string on the plant and the other end on a brick will hold it in place. You can also let the plant float on the water’s surface. WARNING: Water hyacinth is a highly invasive species in areas with mild winters. The plants are banned in several states. Once they enter waterways, the plants grow and reproduce to form dense mats that choke out native species. A thick growth of water hyacinths can snag boat motors and make it impossible to enjoy lakes that are infested. Fish and other animals that live in the water die because the plants block out sunlight and use up oxygen.
Water Hyacinth – Reasons Why and Why Not to Grow Water Hyacinth – Eichhornia crassipes
FAQ
Why are my water hyacinths not blooming?
How to make water hyacinths bloom?
Why is Water Hyacinth illegal?
How long does it take for Water Hyacinth to multiply?
How long do water hyacinth flowers last?
The flowers last until fall and make striking cut flowers. Growing water hyacinth plants is easy. Once established, they require no special care except occasional thinning to keep them from choking out everything else in the pond. Under perfect conditions, a colony of water hyacinths can double its size every 8 to 12 days.
When do water hyacinths Bloom?
Water Hyacinths bloom from late summer to early fall and each plant will produce about 20 flower stalks that reach up to 6 inches (15 cm) tall. The flowers are pale purple and one petal on each flower has a yellow spot. How much sunlight do Water Hyacinths need? Water Hyacinths prefer to grow in a position with full sun and warm water temperatures.
How often do water hyacinths grow?
Under perfect conditions, a colony of water hyacinths can double its size every 8 to 12 days. Water hyacinths need full sun and hot summer temperatures. Introduce them to the garden by scattering bunches of plants over the surface of the water. They quickly take hold and begin to grow.
What temperature can hyacinths grow in?
These tropical plants grow best in full to partial sunlight with water temperatures around 21 to 27°C (70 to 80° F). Water hyacinths can tolerate environmental temperatures from 12°C (54°F) to 35°C (95°F), but both frost and water temperatures over 34°C (93°F) will kill the plant.
What is a water hyacinth?
Beautiful but destructive in the wrong environment, water hyacinths (Eichhornia crassipes) are among the showiest of water garden plants. Flower stalks that grow about six inches (15 cm.) above the foliage arise from the centers of the rosettes in spring, and by the end of spring, each plant holds as many as 20 gorgeous purple flowers.
How to plant a water hyacinth?
Water: in case you are going to plant a hyacinth in a pond or natural pool, it is necessary that the place contains calm water or water with little current. You can also plant this flower in a bulb vase. Lighting: Water hyacinths should be placed in full sun, as they need plenty of light to bloom.