Rubber Tree plants (Ficus elastica) have been a staple of houseplant collections for years due to their fast-growing habits and stunning structural shapes. However, regardless of the fact that Rubber Trees tend to be less temperamental than other Ficus varieties, many people find it hard to keep them properly watered so that they can thrive in their homes.
What is the best way to water Rubber Trees? Rubber Trees prefer to live in moist but not overly-wet soil, so wait until the top inch of soil has dried out before adding any more water to your plant. When it is time, water deeply and thoroughly, but be sure adequate drainage is provided to avoid overwatering.
Rubber Trees are vigorous and tend to be somewhat forgiving, but implementing good watering habits is a sure-fire way to help your plant prosper in your home. I’ve tried to outline what to pay attention to in order to help determine when and how to water your Rubber Tree so that it’s happy and healthy.
How Much Water Does a Rubber Tree Need?
To answer this question, let’s consider the Rubber Tree and where it comes from. Hailing from the rainforests of South Asia, these plants are used to warm, damp climates. These massive trees (in comparison to today’s cultivated varieties) create wide, shallow root systems that sprawl across the forest floors to utilize as much water and resources as possible to support the tall growth necessary to reach the sunlight through the rainforest canopy.
Although not quite the same as their native ancestors, the Rubber Trees in your home very much prefer a similar climate. While they tolerate a wide range of humidity and soil moisture levels, they do well when the soil they are planted in can be kept evenly moist, although not overly-wet.
When I first got my Rubber Tree, this was a hard concept to grasp. Think of it this way: Have you ever put on a pair of jeans from the dryer that isn’t fully dry yet? Like, you felt one of the pant legs, and it seemed dry enough, but when you put them on, you realize the waist and pockets are still damp? Gross, right? Well, Rubber Trees love that feeling!
That icky feeling we get when we are wearing damp jeans is basically what you are trying to achieve in the soil for your Rubber Tree. Keeping the soil evenly moist is their jam, so only watering when the soil is just dry enough is the key to keeping your Rubber Tree happy.
So, what is the best way to do this? Let the top inch of soil dry out completely. You may have to dig your finger in there a bit to make sure it really is dry, but it’s the best indicator that you won’t be overwatering your plants. As you dig in a little deeper, you’ll find that there is still plenty of moisture in the lower soil even though the top has dried out. This is perfect, as most of the Rubber Tree’s roots will still be in moist soil and ready for another watering.
Here’s the catch. Rubber Trees’ watering needs will change slightly throughout a growing season, so allowing the top inch of soil to dry out is always a better practice than watering your plant every Saturday because that just happens to be the day you water.
As much as schedules help us stay on track and get things done, plants operate on their own terms. If this concept frightens all you Type-A people out there, you can always pick up a moisture meter to help determine when to water. A meter can give you a clearer illustration of how moist the soil is, helping you determine the next watering.
The Dangers of Overwatering a Rubber Tree
Like many other houseplants, Rubber Trees tend to react very poorly to improper watering practices. Unfortunately, overwatering is easy to do and can lead to a plant’s declining health or even death.
So, what exactly happens when you overwater a Rubber Tree? Excess moisture saturates the soil the plant is potted in and essentially suffocates the root system. This can cause many issues, but mainly the roots’ ability to uptake water and nutrients, and the process of gas exchange, are hindered, preventing the plant from getting needed nutrients and oxygen. This can also set the stage for disease and root rot to set in, devastating a plant if gone unchecked.
It’s important to note that when I talk about overwatering, I am, of course, talking about actually providing the plant too much water at one time. However, overwatering can also be caused by a lack of proper drainage either in the soil or from the pot itself, causing the retention of too much moisture.
To ensure proper drainage for your Rubber Tree, you should always consider the container they are potted in. Make sure the pot has a drainage hole at the bottom where excess water can flow from, and be sure that the pot is the appropriate size for the plant. Containers that are too big require more soil than is necessary to fill, which holds onto moisture during watering, and can lead to waterlogged soil that takes too long to dry out.
Ensure your soil is light and porous to allow for proper drainage by adding extra pumice or perlite to your soil mixture or incorporating fast-draining potting soil mixtures like cactus or succulent mix.
How to Know When It’s Time to Water Your Rubber Tree Plant
Again, the very best sign that indicates it is time to water your Rubber Tree is by monitoring the top inch of soil to make sure it has dried out. Stick your finger down into the soil. If your finger comes out clean without any moist soil bits stuck to it, you should be fine to water.
I prefer checking the soil often, as it’s easy to do and prevents overwatering. It’s also proactive! Rubber Trees will give you other signs that they need a drink, like drooping leaves or dry leaf tips, but by then, they are desperate, and their health is suffering. A quick check several times a week is the best way to avoid underwatering, as well.
For more information on signs that your Rubber Tree is thirsty, check out this article.
How to Properly Water a Rubber Tree Plants
I know all this watering advice can seem a bit overkill at times, but you’d be surprised at how many people turn to the internet to research what is wrong with their houseplant. And, about 90% of the time, their issue can be attributed to overwatering.
So, what’s the best way to water a Rubber Tree? How do we keep the plant evenly moist? Well, it all comes down to a good old fashioned deep watering.
Many folks tend to water their plants frequently, thinking that a little bit of water more often is the best approach to keeping the soil moist. While it’s true you can do it this way, more often than not, people end up overwatering their plants anyway because it’s hard to gauge how much water is needed, especially if the topsoil is always wet.
Instead, you should water your Rubber Tree less frequently, but deeply. This allows the roots to absorb a sufficient amount of liquid, but then permits the soil to dry out enough so nutrient absorption and gas exchange can still occur. When I say “deeply,” I mean you should pour enough water to evenly wet the soil, allowing the excess to flow from the drainage hole in the bottom of the pot.
This may sound like overwatering, but remember, you should have sufficient drainage in the pot and the soil so that moisture is retained without waterlogging the plant. As the excess water drains from the pot, you’ll have the right amount of moisture in the soil until the top inch dries out and it’s time to water your Rubber Tree again.
Top Watering vs. Bottom Watering for Rubber Trees
Did you know there are two different methods of watering your plants? Top watering is where you pour water onto the soil’s surface in the pot, allowing it to absorb and drain out through the bottom. This is the most common method of watering and is usually a sufficient way to moisten the soil. Just know that if you have a heavy hand, the heavier stream from your watering can might disrupt the soil, and you’ll want to level it out by patting it back into place.
Bottom watering is a method where you place your pots in a shallow dish filled with water and allow the soil to pull the moisture up through the pot’s drainage hole. You’ll know it sufficiently watered when you see that the top of the soil is wet. This method takes longer but tends to facilitate total soil saturation and protect any fragile foliage at the pot’s top.
Both methods work just fine with Rubber Trees. I tend to topwater mine because it’s easier than hauling a big pot onto a watering dish. When I do water, however, I pay attention to make sure the soil is still getting evenly wet, and water isn’t just running down a channel at the side of the pot and draining out the bottom.
If your plant is a bit rootbound and you find it’s not absorbing moisture well from top-watering, you can switch to bottom-watering to ensure the plant gets a nice, long drink until you have the time to repot the plant into a larger container.
Watering in the Growing Season vs. Watering in Dormancy
As I mentioned earlier, Rubber Trees’ water needs will change throughout the seasons, sometimes requiring more water and sometimes much less.
Like most plants, Rubber Trees go dormant during the winter season. This is a time for the plant to shut down its vigorous growth and focus on storing nutrients and expanding its healthy root system underneath the soil. It’s a natural process that is good for the plant, and although its growth is slowed or stopped until the spring, your plant will require very little attention from you, giving you a nice little break.
Because Rubber Trees are vigorous growers, they do require more inputs during their growing season (from early Spring to Fall), so their water requirements are much higher. You can typically expect to water them about once a week, although you should always consider their soil moisture first.
In the winter, when they go dormant, you’ll notice the soil stays damp longer, and your waterings may stretch out to once every few weeks. Again, always check the top inch of soil before adding more water.
What Water Is Best for Rubber Trees?
The good news is that Rubber Trees aren’t very picky about their water. No need to keep a huge backstock of Evian in your cupboard. Tap water is perfectly acceptable to these plants, and really, if we can drink it, most likely our plants will do just fine with it.
If you are not a fan of your tap water and want something a little better for your plant friends, an easy alternative is to leave a pitcher of your tap water out on the counter overnight. This allows chemicals like chlorine to evaporate out of the water, leaving it cleaner for your plants.
If you’re feeling fancy, you can also use distilled water. Distillation removes all of the chemicals and minerals from the liquid, leaving you with very clean water. This is great for plants because the compounds typically found in water don’t build up in the plant or soil. However, most people find that keeping enough distilled water on hand to water their entire plant collection is a bit of a bother.
You may have hard or soft water in your home, which will have an effect on your plants, as well. Hard water is rich in minerals like calcium and magnesium, which typically are good for plants, but if the water is too hard, you can have a buildup of minerals that becomes detrimental, requiring an occasional flush with bottled or rainwater to remove the excess calcium and rebalance the pH of the soil.
Soft water typically has been processed through something like an ion-exchanger, which removes the minerals, but replaces them with salt. Higher salt contents can have a drastic effect on your plant’s health, so you should watch them carefully or consider using bottled water or rainwater to avoid salt buildup in the soil.
Whichever type of water you end up using, make sure it’s at room temperature to avoid shocking the plant. Extremely hot or cold water can physically damage plant structures, especially root systems.
Signs Your Rubber Tree is Overwatered
Overwatering houseplants can definitely happen, even to the greenest of thumbs. Sometimes, though, it can be hard to tell if you’re doing it. Rubber Trees are fairly hearty and don’t often suffer from health issues, but if you notice your plant’s health starting to wane, you should immediately consider the possibility it’s been overwatered.
The most common sign of overwatering is that the leaves, typically starting near the bottom, will start to turn yellow. They can either turn yellow all over at once, or you may notice a yellow/brown spot starting in the middle of the leaf and working its way toward the edges. Essentially, this means that your plant’s root system is sitting in too much water, and absorption of nutrients has been hindered.
Another sign of overwatering is the sudden dropping of leaves. As Rubber Trees grow taller, it is normal for the oldest leaves near the bottom of the plant to start to yellow and drop off. This is due to old age rather than any health issue. However, if you notice a sudden and prolific drop of multiple leaves on the plant, you’ve most likely overwatered, and steps should be taken to remedy the situation.
Remember, your best defense against overwatering is to practice good watering habits. If you notice any of the signs above, your plant is already suffering from too much moisture, and you’ll need to act fast to avoid killing it.
How to Save an Overwatered Rubber Tree
Like I said, overwatering happens, so if you start seeing the symptoms or your plant’s health is declining fast, work quickly to fix the situation.
Step one…stop watering it! This seems like a silly thing to say, but it’s essential to allow the soil ample time to dry out completely, which may take longer than you think it should. Do not even consider watering the plant again until you can verify the top inch or two of soil is completely dry.
If the soil is very saturated in the pot, you may need to repot your Rubber Tree into new, better-draining soil. There is some risk involved in this because you are essentially taking a compromised plant and adding the shock of transplanting it. However, fresh, porous soil is ultimately better for the plant, and it should recover quickly. Be sure the container you use to repot has a drainage hole, as well.
As you repot your plant, be sure to wash away any excess soil and check the roots carefully for root rot. If you see any brown, mushy roots, be sure to cut them away with sharp pruners before replanting.
Sometimes, the rules on watering Rubber Trees can seem a bit complicated, but I hope you now know they are actually fairly straightforward. Don’t water on a “schedule,” but instead check the soil to determine when it’s time. When you do water, do so deeply, allowing the soil to evenly absorb the moisture. And, always make sure your soil and pot have good drainage.
Your Rubber Tree is pretty robust, so there is some room for error, but I promise you that practicing good watering habits is the best way to keep them happy and healthy. In turn, they will appreciate the care and will reward you with some impressive growth and lots of big, shiny leaves.