Dieffenbachias are easy to propagate from cuttings, and under favorable growing conditions, they can grow into a 2-foot-tall palm-like plant in under a year. They are simple to care for, and their tolerance for low light environments makes them popular houseplants.
When growing in deep shade, dieffenbachia’s growth slows down significantly or even stops. Insufficient light is the most common reason for dieffenbachias not growing. To encourage new growth in the spring and summer, give them bright, filtered light, and fertilize every 2 weeks.
There are a few other reasons why dieffenbachias stop growing, like improper watering, being root bound, incorrect potting soil, or not enough warmth.
Here, we discuss the factors that slow down dieffenbachia’s growth and explain how you can get your dieffenbachia houseplant to grow as quickly as possible.
Are Dieffenbachias Slow Growing?
Dieffenbachias are naturally fast-growing plants. They originate from the Caribbean and South America, so they are adapted to growing in warm, tropical environments. Under the right conditions, dieffenbachia houseplants can grow 2 feet per year!
Some people think that dieffenbachias are slow growers because their growth can slow down drastically under certain conditions. For dieffenbachia houseplants to grow in height and sprout new foliage, they need the right care.
Why Dieffenbachias Stop Growing
There are several reasons why dieffenbachias’ growth may slow down or stop, and not all of them are indicative of a problem!
Dieffenbachias stop growing during the fall and winter. It is totally normal for their growth to slow down significantly during the cooler months of the year. Nothing may be wrong with your plant at all. It may just be in a semi-dormant state.
Some dieffenbachia cultivars stop growing when they reach their maximum size. If you have a compact variety that only grows two or three feet tall, the upward growth will stop when it reaches full size. Larger varieties grow six to ten feet tall.
If your dieffenbachia does not seem to be growing during the spring or summer and it has not yet reached full size, there may be a problem.
The most common problems that cause dieffenbachia’s growth to slow down are:
- Insufficient light. Dieffenbachias can survive in low light conditions, but they do not thrive in the dark! If you keep a dieffenbachia in a position where it does not get bright, filtered sunlight, its growth will slow down drastically.
- Improper watering. If these plants get too little water, their growth will suffer. Dieffenbachias prefer their soil to be kept slightly damp. If the soil dries out too much for too long, the plant will not be able to grow. Dieffenbachias’ growth also suffers due to overwatering. If the soil remains soggy all the time, the roots do not get enough oxygen, and they rot. Root rot will cause a dieffenbachia to stop growing and eventually die.
- Insufficient drainage. If you see that a Dieffenbachias soil remains moist even 4 or 5 days after watering, the potting soil may not have enough drainage. Dieffenbachias need a chunky, well-aerated growing medium.
- Lack of nutrients. Growing large, upright leaves requires lots of nutrients, especially nitrogen. If a dieffenbachia does not get enough fertilizer, it is not able to grow taller.
- Root-bound. Dieffenbachias that grow in brightly lit environments grow very rapidly, so they need to be repotted annually. If this is not done, their growth rate will slow down or even stop.
Figure Out Why Your Dieffenbachia Is Not Growing
Before you can address the problem, you must first work out which of the above is the reason that your dieffenbachia is not growing.
It is easy to figure out if the lighting is the issue. Just consider the position that your dieffenbachia is growing in. How many hours of bright, filtered sunlight does it get daily?
To check if soil moisture or lack thereof is the problem, take careful note of how long the soil takes to dry out after you water the plant. If the soil stays soggy for 4 or 5 days, drainage may be the problem.
If you do not normally allow the top few inches of soil to dry out before you water your dieffenbachia, overwatering is likely the issue.
If you do not think you water your dieffenbachia frequently enough, and some of the leaves are yellow or crispy around the edges, then underwatering is likely your problem.
If all the growing conditions are fine, but you have not fertilized the plant in a while, then lack of nutrients may be the reason for slow growth.
If the plant has enough light, water, and nutrients but has been years since your dieffenbachia was repotted, then the problem may be that it is root-bound.
How to Encourage Dieffenbachia Growth
Once you know what is causing your dieffenbachia to grow so sluggishly, take some simple steps to address the issue:
- Ensure that your dieffenbachia lets plenty of bright, indirect sunlight during spring and summer. Move it to a brighter room or nearer to a window. You could also install some artificial lighting and leave it on for 6 to 12 hours daily.
- Water your dieffenbachia thoroughly, let the top layer of soil dry out, and then water again. The hotter the climate and the drier the air, the more frequently you will need to water.
- Ensure that your dieffenbachia’s potting soil is loose, well-aerated and free draining. The perfect potting mix is: potting soil, bark chips, perlite, and coco peat.
- During spring and summer, feed your dieffenbachia every two weeks using an organic, liquid houseplant fertilizer that is rich in nitrogen. Dilute the fertilizer to half strength.
- Repot your dieffenbachia into a container that is only about 2 inches larger than the existing pot. Be very gentle when repotting! These plants are very susceptible to transplant stress. You should also be careful not to get the toxic sap on your hands!
If you notice that your dieffenbachias growth has ground to a halt – do not worry! The reason is most likely insufficient light. To grow optimally, dieffenbachias require dappled sunlight or bright, indirect light. Make sure your dieffenbachia is getting the light it needs.
They also benefit from regular feeding during the growing season. During spring and summer, feed dieffenbachias a nitrogen-rich fertilizer every two weeks. Dilute it to half strength to avoid fertilizer burn. Repot dieffenbachias every year to keep them from becoming root-bound.
Growing up with a mom who filled her home (inside and out) with all sorts of plants, Lisa got her start in gardening at a young age. Living now on her own with a home and yard full of plants (including an indoor greenhouse), she shares all the gardening tips she’s gained over the years.