The reason your water hyacinths are dying is that some aspect of their living conditions is not ideal, and this causes the plants stress.
There are multiple possible reasons for this stress, and figuring out which one is affecting your plants is the first step in fixing the problem.
The most common reasons your water hyacinths may be dying are nutritional problems, low temperatures, not enough sunlight, poor water quality, incorrect water pH, water toxicity and lack of fish.
In this article, we will discuss the different reasons your water hyacinths may be dying and how to save them.
Why are my water hyacinths dying?
Nutritional problems
One of the most common reasons for dying water hyacinths is that the water they are in no longer contains sufficient nutrients. These become depleted over time, and you will notice the plant’s deep green color becoming more yellow due to this.
The roots of the plant dangle underneath the plant in the water where they live. Normally, the water will be rich in nutrients due to organic matter that falls into it, such as fish feces or rotten leaves. Over time, however, especially if there are many aquatic plants in the water, there will not be enough nutrients to go round. Water hyacinths need these nutrients to continue to thrive and survive, so if they are missing the plants will die.
Low temperatures
Stunted growth and aborted leaves are some of the symptoms that can be observed in water hyacinths that have been exposed to cold temperatures. Cold water and chilly air can cause even the healthiest of water hyacinths to become stressed, and even to die.
In the spring, when new water hyacinths are added to a pond, the water may be colder than 60 degrees Fahrenheit. In this case, the plants will likely be stunted and the leaves closest to the base will turn yellow and die.
Not enough sunlight
These plants thrive in sunlight. They also like their water warm, and the sun warms it for them.
Water hyacinths need four hours of sun each day in order to sustain their leaves.
If the plant does not get its required time in the sun each day, it can turn yellow and die. If you want the plants to produce flowers, allow them to get up to eight hours of sunlight a day. If the plants become overcrowded in the pond, this also limits the amount of light that each plant gets, because they end up blocking one another from the light. Ideally, you should only let aquatic plants cover 55-65% of the water’s surface. If the plants do not get their recommended amount of sunlight, photosynthesis cannot take place properly, hence the death of the plants.
Water quality
Water hyacinths like their water neither too acidic nor too alkaline. If the water pH is at either extreme, this can lead to limited plant growth.
The elevated pH levels can cause the plant’s leaves to turn yellow and make it hard for the plant to absorb nutrients from the water. Plenty of incidental materials can cause a shift in the pond’s pH, so make sure you check it constantly for the sake of your water hyacinths as well as your fish.
Lack of fish
Fish and aquatic plants have a symbiotic relationship, whereby the plants provide the fish with shelter while the fish poop provides the plants with the nutrients they need to survive.
If you try to grow water hyacinths in a pond without fish, they will grow, but they will not last. Once the fish are gone, the plants will start to turn yellow and experience the symptoms of nutritional deficiencies.
What are some tips to help keep my water hyacinths healthy?
Trim the plants’ roots
You can do this even before placing the plants in your pond. If there are any dead or yellowing leaves, remove them. Cut off about two inches from the fibrous roots of the water hyacinth. Doing this encourages the growth of new roots and shoots.
After the plants’ roots have become accustomed to their new environment, you can trim the roots every two weeks in the same way.
Skim the pond
As mentioned above, only allow about a third of the pond to be covered with aquatic plants. This coverage is enough for the fish living in the pond and the spacing between the plants is enough so that they are not blocking each other from the sun. Skim the pond regularly for new plants so that it does not become overrun with water hyacinths. Maintaining a harmonious balance in the ecosystem is beneficial to all the organisms present. You can use the skimmed plants to make organic fertilizer.
Check their growth
If the plants start to grow excessively, this can suffocate the fish and other creatures inhabiting the pond. Water hyacinths can add a significant amount of new growth in just two weeks, so keep an eye on the spread of your plants at all times.
Do not use algae killers
You may be tempted to use algae killers or other chemicals to enhance your water hyacinths, but try to refrain from doing this. If the leaves of your water hyacinths turn yellow during the summer, it is best to simply use a fertilizer that is safe for both fish and other aquatic plants in your pond. After a few days, you should be able to see new growth on your plants.
Winter care
In the winter, the plants may turn yellow because of the cold temperature of the air and the pond water. It is no surprise that some people have a problem keeping their aquatic plants alive during the winter.
You can avoid this situation by isolating your water hyacinths in aquariums before winter arrives. A simple aquarium that holds six inches of water will do just fine.
Conclusion
Water hyacinths make a great addition to your pond, both for the benefits they can provide your fish as well as for their aesthetic appeal.
There may be instances when your water hyacinths are looking yellow or pale, and even seem as though they are about to die. This means there is an environmental factor present that is causing the water hyacinths stress. If you are able to figure out what exactly is affecting your plants, treatment will be much easier.
The most common causes of dying water hyacinths are nutritional problems, low temperatures, not enough sunlight, poor water quality, incorrect water pH, water toxicity and lack of fish.
Image: istockphoto.com / Helge Masch