Ficus trees (Ficus
Why is my
Read through the following common causes of leaf drop to get a better understanding of why your
Common Causes of Leaf Drop
The ficus tree, (Ficus
Problems arise when growing ficus trees indoors since they originated in subtropical areas with very distinct wet and dry seasons. Changes in their native climate signified the plants needed to prepare for an upcoming dry season when water would be scarce. They acclimatized to this impending water scarcity by dropping leaves to reduce the amount of foliage the plant would need to support.
Now, when grown indoors and faced with fluctuations in care or climate, the plants drop leaves as a survival mechanism, brought on by their natural evolution and adaptation to outdoor growing conditions. It’s not unusual for plants to drop upwards of 20% of their foliage when trying to adjust to changing conditions brought on by abiotic or biotic stressors.
Variations in watering, light exposure, and temperature, as well as pest and disease problems are the most common stressors triggering leaves to drop from ficus.
Inconsistent Watering
Figuring out a good watering schedule is a tricky task when growing a ficus indoors and the primary reason most owners see leaf drop. Too little water will cause leaves to drop. Too much water will also do the same. The best thing to do is to maintain a consistent, even watering schedule during the active growing season in the warmer months and a reduced, albeit still consistent, schedule in the cooler winter months.
Underwatering
One of the most common reasons for a ficus to drop leaves is not receiving enough water. These finicky plants do not like to hang out in wet conditions but instead, prefer to be planted in well-drained growing media when grown in containers. However, there’s a fine line between letting them get dry enough between waterings and getting overly dry.
The reason your ficus drops leaves when underwatered is related to its evolution. It drops leaves to prepare for the dry seasons that occur in its native habitat, to reduce foliage that needs moisture to live. When they don’t receive enough water when indoors they think a dry season is coming and drop leaves in response.
Ficus are quick to react if you let the growing substrate in their container get too dry. Never let more than the top couple of inches dry out between waterings.
Overwatering
Just as damaging as underwatering, overwatering your ficus tree can cause significant leaf drop especially in the winter months. When plants are overwatered it prompts a condition called root rot to develop. Soggy, oxygen-depleted soils encourage the growth and multiplication of Pythium, Phytophthora, Rhizoctonia, or Fusarium fungi which spreads into the roots, infecting plants. Healthy roots begin to turn brown and mushy as they perish, unable to take in nutrients needed for growth.
The challenge with root rot is that it often goes unnoticed because it occurs beneath the soil surface and out of sight. Symptoms will show first on the roots causing them to turn brown and mushy — classic signs of rot. As root rot progresses leaves turn yellow, wilt, or droop and then become mushy as well.
Once symptoms are visible in the leaves the problem may be past the point of rectifying, endangering the entire plant. In extreme cases when conditions are perfect, i.e. in pots without drainage holes, root rot can kill the whole plant within ten days.
If root rot is caught soon enough remove as much of the soggy soil as possible adding in fresh, clean potting soil. If root rot has spread significantly, dissect the plant, keeping only the healthy portions. If the whole base is affected, it may be best to dispose of the entire plant.
Changes In Environmental Conditions
Environmental variations are another major reason your ficus tree may drop leaves. As the temperature changes and day lengths shorten your plant will gear up for what it thinks is an impending dry season, triggering survival mechanisms.
Change In Season
The normal transition from one season to the next will also cause your ficus to drop leaves as it adjusts to differences in sunlight, temperature, and relative humidity. These conditions vary less within the home than outdoors but still enough the plant feels the need for acclimatization.
Leaf drop will be the most extreme as homes move from fall to winter. Day lengths continue to shorten, temperatures drop in response (most homes are kept cooler in the winter than the summer), and the relative humidity levels plummet as winter takes hold. This is when the plant naturally thinks the dry season is approaching and drops leaves to use resources such as water more efficiently.
Too Little Light For Your Ficus
Native to tropical areas, ficus trees thrive in full sun locations and require high amounts of sun exposure when grown indoors. Reduced lighting as the days get shorter will result in leaf drop, as well as limited exposure to the sun in your home in general. Make sure to keep windows clean to allow as much light in as possible and watch for curtains or blinds that may be obstructing light coming in through the windows.
In the summertime, if possible move your ficus outdoors to allow access to maximum sun exposure. Keep in mind though that when you bring it back indoors at the end of the summer you will see leaf drop then as the plant works to acclimatize.
Ficus Trees Don’t Like Drafts
Many houseplants are sensitive to the drafts in homes coming from leaky windows, or register vents blowing heat in the winter and cool air in the summertime. These drastic swings in temperature trigger that survival mechanism in plants, resulting in the dreaded leaf drop. Try to maintain as even an ambient temperature as possible with no more than a 5 – 10℉ swing in temperature.
Insect Pests
Encountering trouble with pests is a sure bet your ficus will start dropping leaves, as a stress response to the infestation. The three most common insect problems are scale, mealybugs, and spider mites — all problematic in most, if not all, houseplants. Pest problems tend to rise as you turn your heating system on as temperatures drop in the fall.
Regardless of the type of insect problem mechanically removing insects by hand is an appropriate treatment option when dealing with smaller sized ficus plants grown indoors. Heavily infested stems or branches should be pruned off the ficus tree and discarded to prevent the spreading of the infestation. Trees can also be sprayed with neem oil, a naturally occurring pesticide.
Scale
Scale is a threat to most species of shade and fruit trees and ornamental shrubs. The pests pierce leaves, stems, branches, and tree trunks to feed on the sap within these plant tissues, damaging the plant overall.
There are two different types of scale insects that infest ficus trees: soft and armored scale. Both appear as little brown bumps on ficus leaves with soft scale being more prevalent. Insect sizes range from ⅛ to ½ inch in length; color, shape, and texture vary amongst different species.
Soft scale insects do not possess a hard, protective coating so they generate either a thin, powdery, cotton-like or waxy layer over their bodies for protection. These layers cannot be separated from the insect body. Armored scale, on the other hand, create a hard shield-like layer from shed skins and wax to protect themselves from natural predators and chemical insecticides. This layer can be separated from the insect body and tightly adheres the scale to the plant forming a waterproof seal.
Besides the notorious left drop, ficus plants infected with scale exhibit yellowing leaves. The yellow spots appear on the tops of the foliage while the insects suck sap and chlorophyll from the bottom. Leaves may wilt, become stunted, and you may see decreased vigor overall in the plant. To tell the difference in types of scale look for honeydew secretions; soft scale secrete a large amount of honeydew, armored scale do not.
Mealybugs
These pink, soft-bodied insects are covered with a white, waxy, almost cottony-like material. The cottony fluff protects them from moisture loss and excess heat. Mealybugs are usually found in colonies in somewhat protected areas of the ficus such as on the leaves close to the crook of the branches.
Mealybugs are similar to their relatives the soft scales but they lack the scale covering and retain legs throughout their life cycle allowing them to move around.
Symptoms show as stunted or deformed leaf growth, especially on new foliage as mealybugs inject a toxin into leaves when they feed on the plant’s fluid. They also excrete honeydew as they feed, encouraging the growth of sooty mold.
Spider Mites
These tiny sucking pests are found on the undersides of leaves, wreaking havoc on indoor houseplants. Spider mites feed on the fluids found inside the leaves of ficus plants, piercing the waxy coating to access the internal fluids.
One of the biggest challenges with spider mites is their prolific nature; often times a heavy infestation will occur, unnoticed, before plants begin to show physical symptoms of damage.
With an infestation of spider mites, leaves may be stippled with discoloration or turning yellow overall. Plants may also exhibit a fine, spider-like webbing between the leaves or at the base of the plant.
Bacterial Diseases & Fungal Infestations
Stress from bacterial diseases and fungal infestations will cause ficus leaves to drop too. Crown gall, leaf spot, anthracnose, and southern blight are the most common problems.
Crown Gall
When your ficus is infected with crown gall, tumor-like lesions commonly known as galls, form on the surface of stems or internally within the stem tissue. Often times a simple wound on the plant will allow entry of the infestation into the plant but is dismissed as many think the initial swelling is simply a callus forming as the plant heals itself. As the infection progresses the swelling becomes irregular in shape and begins to turn dark brown or black as the plant cells perish.
If plants show symptoms of crown gall, the affected plant tissue must be removed using sterilized equipment a couple of inches below the gall. There are no known, effective, chemical treatments.
Leaf Spot
There are a number of different species of leaf spot that ficus plants are susceptible to. Pseudomonas Leaf Spot, Xanthomonas Leaf Spot, Corynespora Leaf Spot, and Myrothecium Leaf Spot are the common forms. All of these pathogens favor warm, humid conditions and cause circular or angular water-soaked lesions on foliage.
To prevent leaf spots avoid getting foliage wet when watering ficus plants; treat with a copper-based bacteriacide or remove infested leaves once symptoms appear to minimize plant damage and spreading to neighboring houseplants.
Anthracnose
A fungal disease, anthracnose is characterized by necrotic spots on the leaves and commonly causes tip dieback in ficus plants grown indoors. This disease occurs more frequently in warm, humid conditions like leaf spot, but often follows tissue damage from other causes.
There are a number of fungicides that can be used to effectively treat ficus plants once anthracnose is observed.
Southern Blight
Like the other diseases and fungal problems, the southern blight fungus grows rapidly when soils are wet and temperatures are hot. Symptoms start off as a fine, feathery white or brown (depending on the fungal variety) mycelium mat on the surface of the growing media that then make their way onto plant parts. Eventually, the mycelia form small seed-like, brown structures called sclerotia. The sclerotia are used by the fungus as protection to survive unfavorable conditions such as lack of moisture and heat and are resistant to penetration of fungicides.
Once southern blight symptoms appear in plants it’s best to dispose of the ficus entirely and treat any neighboring, unaffected plants with a fungicide drench as a means of prevention.
Fertilizing
Lastly, fertilizing can cause severe leaf drop in indoor ficus plants. While most houseplants appreciate a dose of all-purpose fertilizer every four to six weeks during their active growing season, ficus trees don’t like being fed regularly. If you do want to give them a dose of fertilizer make sure to feed plants early in the spring as they begin growing again after the cooler, winter months. Mix an all-purpose, slow-release fertilizer at about one-half the strength recommended on the label and apply when the
Caring For A Ficus
Now that you understand the common reasons why your
- Water consistently. Adjust moisture levels to the season but then maintain an even watering schedule even the next seasonal change. Give your ficus more water in warmer months when the plant is actively growing and less water in the winter when the plant is growing at a much slower rate.
- Light exposure is critical. Native to outdoor locales, a ficus will soak in as much sun as you can provide it. Try to find a location within your house that has bright, albeit indirect light for as much of the day as possible. Avoid direct sunlight as it can scorch leaves.
- Pruning is needed to keep plants from getting unruly and taking over space within your home. Remember, these plants are known to grow to towering heights when outside; if growing conditions are optimum these beauties will take off and grow, grow, grow. Prune in the spring as new growth is occurring to reduce stress on the plant.
- Repot frequently to prevent roots from becoming rootbound within the container. Prolific root growth occurs when ficus are given sufficient sunlight and the proper amount of water.
Can you be allergic to ficus trees?
Yes, ficus plants are a common allergen within homes, especially irritating to those with asthma or other pulmonary complications. People allergic to latex should also be wary of ficus plants as they are related to rubber plants.
This website is filled with useful tips for growing and caring for your houseplants. If you want to find out about some great resources that can help you look after your indoor plants, check out my recommended resources section. This will help you choose the best books, tools, and resources to help you develop your green thumb.