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If you are new to the world of sundews or drosera, one of the things you have to learn right away is watering. Sundews need a lot of it, but too much can result in mold or even root rot. In this article you will learn how to properly water sundews and if sitting the pot in a tray of water is a good idea or not.
Sundews thrive in moist soil and humid environments, so sitting the plant in water is fine. The water level should be half the height of the pot. So if your sundew is in a 4 inch pot, the water level should be 1 1/2 to 2 inches high.
How to Sit a Sundew in Water Step by Step
Sundews prefer moist soil, and the best way to do that is to sit the plant in water. The easiest method to doing this is to use a tray.
The steps are as follows.
- Sundews need pure water. You can also collect rainwater, though that is not practical during summer. Any type of water as long as it is free of minerals will be fine. We recommend Ice Mountain Spring Water as it is 100% safe or carnivorous plants.
- Get a tray that is taller than the sundew pot. If you have several sundews, the tray has to be large enough for all of them. Each pot should be a few inches distant from the other.
- Fill the tray with water until it is half the height of the plant container. This does not have to be exact.
- Note: if growing seeds and the atmosphere is dry, put a plastic wrapper over the tray to keep the moisture in.
The water level does does not have to be exactly half the container height. During summer you can add a bit more. But you should start with a lower level as it is easy to add more if necessary. Too much water can cause mold to appear.
All you need to do now is refill the tray. You can wait until the water level is down to 1/4 inch or so, just do not let the soil dry out.
At least once a month you should water the sundew from the top. Do not pour too much, just a sprinkling to eliminate any mineral buildup or food bits that may have fallen into the soil.
You should also dry the tray monthly to keep water from stagnating. This also helps prevent fungus and diseases from spreading. While the tray dries out, water your sundew (if necessary) to keep the soil moist.
How Much Water Should I Use For Sundews?
Sundews can live for years if properly cared for. There are a lot of factors that affect its lifespan, and water is certainly one of them. The question is, how much water is too much? Where do you draw the line?
Sundew water requirements vary from season to season. You should water sundews as much as needed to keep the soil constantly damp.
So during summer you might need to refill the tray twice a day or more, depending on how many sundews you have. Refilling will be less frequent during the other seasons and if it is humid in your location.
Sundews need more water than the average houseplant so the tray method works especially well. Unless you filled the tray to the brim, your sundews will be all right.
If you are not sure how much water your sundew needs, check the soil. If it is moist, there is no need to add any more water. If the soil is dry, water it. Not sure if the soil moisture is correct? The Sonkir Soil PH Meter provides accurate soil moisture readings for your plants.
Frequency is irrelevant as it will vary depending on the season, humidity, temperature, climate etc. But the need for constantly damp soil is always there.
Water Types You Can (and Cannot) Use
Tap water should be avoided because it can be fatal to sundews. The minerals could accumulate in the soil and spread throughout the plant. Many use tap water since it is widely available, but it bad for sundews in the long term. The types of water for sundews are:
- Rainwater. If it rains frequently in your location, collect the water. This is as natural as it gets and free as well. Of course this is only possible during the rainy season so if you live in a dry, arid place, check the other options below.
- Distilled / purified/ spring. The cost of distilled water has dropped significantly so it is more affordable now. You can buy them online and they are well suited for sundews.
- Reverse osmosis. Reverse osmosis water works fine for sundews, but they are not as widely available as distilled water.
It is hard to emphasize how important pure water is for sundews. It can literally mean the difference between a healthy, colorful plant with plenty of leaves and dew, and a sickly, dying one. So resist the urge to use tap water and instead try any of the above mentioned instead.
How to Remove Mold in Overwatered Sundews
Mold appears when sundews are overwatered, but it is easy to remove. The key is to get rid of the mold as soon as possible to prevent its spread.
- You can easily see soil mold by their green, brown or white color.
- Wear a mask first, then use a spoon or another tool to remove the mold.
- Go over the plant thoroughly. Remove any mold on the leaves. Prune any leaves that have a lot of mold. When you have removed all the mold, apply anti-fungal treatment. Follow the instructions for its application.
- Repeat the steps above for all your sundews with mold. Repot your sundew if there is a lot of them.
While the steps above will work for any sundew, prevention is always better. Follow these steps to keep mold away from your plants.
- Do not overwater sundews. As long as the soil is damp, you do not need to water the plant. If mold appears, cut back on the water.
- Sundews with sufficient exposure to light can prevent mold. Sunlight and good air circulation are essential for healthy sundews.
- Do not let water stagnate. This is why you should clean the tray and replenish the water. Mold, fungus and bacteria thrive in stagnant water so keep it fresh.
- Feed your sundews. If your sundew is outdoors and eats bugs regularly, it will be resistant to mold and infection. But if it is indoors with no access to insects, make certain to feed it at least once a month. Here is a guide on how to feed sundews.
- Remove dead leaves and debris. Prune your sundews and remove food bits and other debris on the soil.
How to Water Sundews
So sitting sundews in water is fine, but you also have to do a few other things to keep your plant in good condition.
- Shade the plant if there is too much heat. Heat will evaporate water quickly and could burn the leaves. Move the plant to another location to avoid direct sunlight.
- The pot has to be at least 4 inches tall. If the container is too small, the roots will not have room to expand. This might cause problems later on.
- Sundews can adapt to different environments, but if it is very hot and dry, a humidifier will help.
- A typical drosera eats four times a month. Digestion for each meal takes about a week so there should be at least one tentacle curled up all the time. If the plant is not eating, it could be due to lack of water.
- Lack of water may also lead to lower dew production. If you do not see any of the sticky stuff on the tentacles or leaves, it could be because the sundews need more water, light or both.
- Do not touch or play with the plant. Doing so puts it under stress.
Sundews require plenty of water but it is possible to overdo it. Aside from using the right amount, the type of water you use is just as important. With the information in this guide you should be more confident about watering sundews.
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.