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Root rot is a condition that can afflict any plant and that includes sundews. Unless taken care of, this disease will spread rapidly and could be fatal to the plant. Fortunately there are ways to find out if your sundews have root rot and what remedies are available.
Sundews can develop root rot if it is overwatered or has poor soil drainage. The symptoms include brown or black leaves, little to no dew and tentacles curling even without eating.
Symptoms of Sundew Root Rot
The most common signs of root rot are lack of dew and the tentacles folding over even without food. Lack of dew (scientific name mucilage) is a general indication something is wrong with your sundews. But if the tentacles curl up, it probably has something to do with the roots.
Root rot also turns the leaves brown or black. The decay starts from the roots but eventually makes its way up to the leaves. By this time the disease has spread to various parts of the plant.
However it is hard to diagnose root rot since the roots are in the soil. The only time you will know is when the leaves turn brown, tentacles curl and dew production stops.
As the rot spreads, plant growth slows or stops. Afflicted sundews will not eat anything, not even aphids which is part of their diet. Sundews lose their color, vibrancy and just look unhealthy.
Root rot can kill the plant if not handled immediately. Nearby plants might also be affected so you have to act quickly.
What Causes Root Rot in Sundews?
Too much water and poor drainage are the most common causes of root rot. There are other possible reasons however.
- Pot is not deep enough
- Water level is too high
- Soil is overwatered
- Sudden drop in temperature
- Improper soil mix
- Poor soil drainage
- Fungal infection
Water Level is Too High
If you are using the tray method, use a deep container. For a 5 inch pot, the water level should be 1 inch, for a 10 inch pot, 2 inches of water. Some sundews will be fine with only 1/4 inch water, so before you buy a drosera ask the vendor how much water is required.
The taller the pot you use, the higher the water level possible. If the pot is too tall you risk drying out the plant. Start with an inch of water and check the soil. It has to be moist, not dripping with water. Use only distilled or purified water so contaminants do not get into the soil. We reconmend Deer Park Spring Water as it is fresh and natural.
Overwatered Soil and Temperature Drop
While sundews require plenty of water, do not overdo it. The excess water will seep from the soil down to the roots and cause rotting.
Overwatered soil also makes the roots vulnerable to fungal infection. This will make things worse for your sundews. If the water is not removed, the roots will turn mushy and collapse, killing the plant.
Sundews will not develop root rot with a sudden temperature drop. But this does make the plant more vulnerable. If you overwater sundews during summer, chances are it will harm the plant as the roots will soak the liquid.
But if soil is overwatered, colder temperature will worsen the situation. The water will stagnate in the soil and accelerate the decay. The lower the temperature, the faster water will work its way into the roots.
Poor Soil Drainage
Sundews prefer poor soil mixtures like 1:1 peat moss and perlite. But you have to make sure the soil drains properly, otherwise this could precipitate root rot and other problems.
Soil drainage refers to the natural movement of water in soil. Water goes through and out of it. If water gets stuck in the soil, it ends up in the roots, leading to rot. Poor drainage is exacerbated by drops in temperature so keep an eye on that too.
You also have to use the right type of soil. As mentioned peat and perlite are good for sundews. But you can also use Doter Sphagnum Moss Potting Mix as it is good good for sundews and other carnivorous plants.
How to Treat Sundew Root Rot
If you see any of the symptoms above, is it possible to save your sundews? If you catch the root rot early, yes it is.
Once the entire root is infected, sundews cannot be saved. But if some parts are healthy, cut off the rotting roots and leaves. Take the remaining healthy roots and repot the sundews.
If you suspect root rot, isolate it from your other plants. Press your hand into the soil so the plant comes up. Carefully pull up the plant as you remove the soil.
Examine the roots. Rotting roots are soft and mushy whereas healthy ones are firm. Get a pair of sharp scissors or pruning shears and cut the decayed parts. Remove any brown or blackened leaves too.
Get a new pot, at least 6 inches deep and prepare a soil mixture. The 1:1 perlite and peat moss will be fine though you can also use 1:1 sphagnum moss and silica sand. Either way, plant the sundews.
Get a tray and put the pot there. Pour a quarter inch water into the tray. Ensure the plant receives 8-12 hours of light every day. If you were able to remove all the rotting parts, the plant will recover.
Once the tentacles start opening up again, your sundews are on the way to recovery. Soon enough it will start producing dew. Do not touch the dew as that could harm the plant.
How long the plant takes to recover will depend on the severity of its condition. But if you were able to remove the rotting areas and provide with plenty of light, water and air circulation, it will be fine.
When the tentacles start to unfurl, do not just feed it yet. Wait until you see dew on its tips, then you can start feeding. You may want to give it some dead bugs or freeze dried mealworms until it is strong enough to catch insects on its own.
How to Prevent Sundew Roots From Rotting
While sundews can recover from root rot, prevention is always better. The following are some of the steps you can take to avoid root rot.
Use good draining soil. Make sure you mix the soil properly. Add enough water. Do not use rich, fertilized or enhanced soil.
Use pots with sufficient drain opening. The drainage hole will prevent water from clogging up the roots. The pot has to be large enough to accommodate the roots as it expands. Move the plant into a new container if it has outgrown its pot.
Do not overwater. Instead of wondering how often you should water, use the tray method. Make sure you fill the tray with an inch or so of water. Add more if you have a large plant or deep pot. When the water level goes down, refill it. Clean the tray every now and then to prevent liquid stagnation.
Use purified water. Distilled or spring water is ideal for sundews and other carnivorous plants. Tap water might contain elements that weaken roots.
Provide several hours of light. All houseplants require light and sundews are no exception. This is particularly true for sundews that are recovering from root rot. Natural light is preferable but you can also provide artificial light.
Improve airflow. Airflow is good for sundews and reduces the chances of fungal infection. Proper airflow, sunlight, water and good soil drainage are the ingredients necessary to counter root rot.
Do not feed sundews with human food. Sundews cannot digest hamburger, steak or other human food. Forcing them to eat it will just weaken their internal workings, including the roots. Stick with insects, freeze dried worms and fish food.
Do not fertilize the soil. Rich soil can kill sundews. Their roots thrive in nutrition poor grounds and they can get nutrients from bugs. Use only the right soil mix and of course the right pot size.
Root rot is a serious condition and needs to be handled as quickly and efficiently as possible. So it is important that you know what can cause root rot, how to prevent it and how to deal with this in case your sundews get afflicted.
My fascination with carnivorous plants began many, many years ago with Venus Fly Traps. Now I am more than happy to impart what I know with other enthusiasts and those who are curious about meat eating plants.