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You may not know much about dieffenbachia, but whether you realize it or not, you’ve probably seen one at your local home improvement store or nursery. You may have heard it referred to as dumb cane, which is an interesting name for any houseplant, but makes sense when you understand where it comes from.
Despite the strange nickname, whether it’s on your back porch or next to the side table in your living room, dieffenbachia grows just like any other common house plant, and as potted plants grow, they need to be repotted.
In this guide, you will learn everything you need to know to safely and successfully repot your dieffenbachia plants.
What Is Dieffenbachia?
Dieffenbachia is a hardy house plant known for its exotic and attractive foliage and unique flowers. It comes in several different varieties, ranging in different heights, and also has several common names including, dumb cane, mother in-law’s tongue, and leopard Lilly.
Dieffenbachia is a genus of flowering plants in the family Araceae. To many, the dieffenbachia may also simply be known as the window plant, as it usually ends up next to a window throughout its life—interior designers might agree!
The species name honors Joseph Dieffenbach, the head gardener of the Botanical Gardens in Vienna who passed away in 1863.
Despite its curious names, it’s used widely as a decorative plant, but it is also toxic, making it somewhat risky to keep around if you have children or curious pets. Nevertheless, they will only temporarily prevent speech if ingested.
Despite this, the dieffenbachia is low maintenance, as filtered sunlight through a window is sufficient enough to promote growth, as long as it’s watered regularly (but not too much).
Over time, the roots will expand to the point of filling the pot almost entirely, leaving little to no room for further growth—this is usually when repotting comes into play.
Repotting puts plants under a great deal of stress in some cases. It depends on how much you trim, how long it’s out of the soil, as well as other factors.
Repotting is the process of removing your plant from the pot it is currently occupying, removing any and all residual soil from the pot and the root system, and placing your plant back into a new pot with fresh soil.
The purpose for repotting a plant varies from case to case. Sometimes, fungus might be growing in the roots, other times, insects or other pests might have infested the soil, and still other times the plant is simply outgrowing its pot and requires more room to grow.
Repotting gives you the chance to see what’s beneath the surface. If it’s been a long time since you’ve repotted your plant, and it’s showing signs of yellowing, fading, or drooping, you should first make sure that it’s getting enough sunlight and water.
However, if those are helping things along, then it might be time to repot your dieffenbachia. Repotting gives you the chance to cleanse the roots of whatever harmful substances it was submerged in, and replace its soil with a fresh and nutrient-rich mixture.
When to Repot?
Whether you’re an avid gardener or a first-time hobbyist, it’s important to know when to repot your dieffenbachia. Determining the best time to repot comes down to a few simple things.
Not everyone has a lot of space to keep their house plants. Some people might have large windows for keeping multiple plants inside, providing plenty of sunlight, whereas other plant enthusiasts might only have space in a corner, or up in a small window sill.
The amount of space you have available will determine the size that your plant will be able to grow—which is directly connected to the size of the pot you keep it in.
The dieffenbachia can range from three to six feet in height, and one to three feet wide. This is a pretty big range of sizes, and while some are genetically predisposed to growing taller or wider, the size of the pot you choose will affect the amount it grows.
If you don’t want your plant to grow more, you should stick to a smaller size, but this will be covered more later on.
If you’ve just purchased your dieffenbachia, it’s possible that the pot is too small for sustainable growth to occur. In this case, it’s best to repot the plant as soon as possible. When purchasing the plant, take note of the size and purchase a new pot and a proper potting soil mixture while you’re already at the store.
If you’ve had your dieffenbachia for a while already, it’s possible that the root system has grown too much and is now filling out the existing pot. In this case, you should repot using a larger pot.
After you’ve repotted once, you won’t need to do it again for another two to three years. The best time to repot is always during the springtime, as the daylight is optimal for new growth and flowering during this time of year.
What Size Pot to Use
All plants need a certain amount of light to survive, so it’s important to know what size pot to use.
Dieffenbachia plants prefer medium or subdued light, which means they’ll grow in a large pot. This plant also grows well in bright indirect light, but it needs more water than other plants and will drop leaves if the watering is too low.
The size pot that you use will be determined by the size of your plant. The larger the plant, the larger the pot.
Some dieffenbachia varieties can grow up to six feet tall, so they’ll need larger pots. For these, it’s best to provide them with a pot that has a 12-to-16-inch diameter. This allows the plant ample room for root stabilization and water retention.
Small to medium-sized varieties of dieffenbachias proportionally require less pot space. For smaller and medium-sized varieties, you should stick to a pot with a diameter of no less than six to eight inches.
Over time, they might begin to outgrow these pots, which is normal, but it’s crucial to keep your dieffenbachia in the proper size pot.
If you use a pot that’s too big, the excess soil will retain much more moisture, putting your plant’s delicate roots at risk for developing root rot. Another possibility is that if your dieffenbachia is in a pot that is too large, it can become root-bound.
This essentially means that your plant will focus its growth into the soil instead of upward in the direction you want. Root-bound plants appear to be stunted and don’t appear to grow.
Avoid this by using a pot of the proper size as already discussed.
How to Repot Dieffenbachia
If you’re a first-time plant owner, repotting might seem a bit unsettling. Ripping your precious plant from the ground and depriving it of soil, while potentially damaging sensitive roots and placing it under stress sounds like a job for more practiced hands, but in reality, it’s something that anyone can successfully do as long as they follow some basic steps!
The first thing you should keep in mind when repotting your dieffenbachia is safety. All parts of the dieffenbachia are toxic. They contain calcium oxalate, which forms as tiny needles (known as raphides) all across the outside of the plant.
These can cause physical pain, as well as swelling and irritation when handled improperly or ingested. These raphides release proteolytic enzymes, which make things worse for the victim, leading to symptoms such as respiratory distress and the inability to speak, especially when ingested orally.
Whether you’re repotting garden flowers or dieffenbachia, you should be wearing gloves to prevent contamination and the spread of potentially infectious bacteria that could harm the plants. So make sure you put on a pair of gloves before you start!
Whether you’re repotting your dieffenbachia for the first time or the fifth time, it’s a good idea to use a pot that’s one size larger than the previous pot. This will allow the roots to continue growing at a controlled rate, and prevent the plant from becoming root-bound.
It’s important to note that plastic pots retain water better than clay, which might be ideal if you prefer to water less. With more moisture available in the soil, you won’t have to water as much.
In either case, whether clay or plastic, it’s important to make sure that the bottom of your pot has holes for water drainage. While some moisture is good to be left in the soil, too much will lead to root rot—which will kill your dieffenbachia.
Once you have a new pot selected, make sure you have a proper soil mixture prepared for repotting. The soil should be composed of mostly organic materials, somewhat loose and well-draining, but should be able to retain moisture (not sandy).
Some examples of good dieffenbachia soil mixtures include equal parts peat and perlite, or equal portions of vermiculite, soil, and peat.
After preparing the soil mixture, carefully remove the dieffenbachia from its current pot and soil. With your hands, carefully untangle the roots, removing soil until all that’s left is the plant and its roots. It doesn’t need to be perfect, as long as most of the soil is removed.
Then fill the new pot a quarter of the way with fresh soil, place your dieffenbachia in the new pot, and fill it the rest of the way with fresh soil, packing down around the sides as you go—just make sure it’s not too compacted.
Be careful not to repot the dieffenbachia too deeply, as it will put the plant under even more stress. Once it’s repotted, water the plant until you see water flowing from the drain holes in the bottom.
The Best Place to Keep Dieffenbachia
After you’ve repotted your dieffenbachia, it’s important to make sure that it receives enough sunlight, as it needs the energy to recover from the stress of repotting. However, it’s best to keep them out of direct sunlight.
Avoid keeping it near a radiator, as dieffenbachias are tropical plants that need moisture and humidity to thrive. However, the leaves will turn yellow if it’s overwatered. They will also become more pale and white if they need more light.
Tips on Caring for Dieffenbachia
As already discussed, dieffenbachia are fairly easy to take care of and are a good option for both beginners and avid plant enthusiasts alike.
They require soil that drains well but also retains some moisture, such as a mixture of equal parts peat and perlite—the organic materials that make up peat help retain moisture for the plant, and the perlite helps with proper drainage.
You should keep your dieffenbachia in a properly sized pot, as a pot that is too small will prevent it from growing, even causing it to wilt in some cases. A pot that is too large will also lead to problems such as root rot and the plant becoming root-bound and being stunted in its growth.
Dieffenbachia requires little regular watering—once or twice a week is sufficient for healthy growth. Any more and it’s possible that the leaves of the plant will soften and begin to turn yellow.
Dieffenbachia also requires ample light, but not directly from the sun. Direct sunlight will scorch the leaves and cause them to turn yellow and brown. It’s best to keep them in a window that receives plenty of indirect sunlight.
Typical Problems with Dieffenbachia
The most common problem with any house plant is overwatering. Dieffenbachia needs moist soil, but if it receives too much water, resulting in soggy soil, it will harm the plant. If your dieffenbachia is turning yellow, check your watering schedule. You should water it no more than twice in a week.
Another common problem is excessive sunlight. Make sure it’s getting indirect sunlight to avoid scorched leaves.
Caring for a dieffenbachia isn’t a difficult task. Just about anyone can do it. Repotting is an essential part of this, as it provides the plant with more space to grow, and extra nutrients from fresh soil.