When I first started growing citrus trees, I didn’t have a clue what I was doing. I remember my lemon tree started losing leaves during the fall, which I thought was normal since some other trees do it. But, I wanted to be sure, so I did some research to find out if citrus trees lose their leaves seasonally, or if they’re evergreen. Here’s what I found.
Citrus trees are evergreen and retain the majority of their leaves throughout the changing seasons. As evergreen trees, they don’t go dormant in the colder months and are less suited for cold climates. Citrus trees also have smaller leaves than deciduous varieties, as they do not conserve much energy during winter.
So, how do citrus trees differ from deciduous trees? What should you do with them in the winter? And why is your citrus tree shedding leaves even though it’s supposed to be evergreen? Let’s explore the answers to these questions and more!
Are Citrus Trees Evergreen or Deciduous?
Citrus trees are classified as evergreen and not deciduous. These trees stay green year-round, as their name suggests. The change in seasons doesn’t affect their foliage, which causes them to require a high level of light year-round to continue nutrient production.
In comparison to deciduous trees, evergreen trees usually have smaller leaves because they do not need to conserve large amounts of energy over the winter. Citrus trees don’t have true dormancy periods like stone fruits or other deciduous varieties.
Although they don’t go dormant in the colder months, their growth will be slowed to conserve energy. Besides citrus trees, other examples of evergreen trees include pine and oak trees.
In contrast, deciduous trees lose their leaves in the fall and regrow them in the spring to help them withstand the harsh weather.
Deciduous trees also have a high water conservation ability and broad leaves for maximum nutrient production. Losing their leaves allows them to go into a dormancy period to make it through the winter. Some examples of deciduous trees include elm, birch, and apple trees.
Do Citrus Trees Lose Their Leaves in the Fall and Winter?
Citrus trees may lose some of their leaves in the fall and winter as part of their natural leaf cycle. This process is a slow and gradual replacement, but the most shedding usually happens in fall. If a citrus tree undergoes excessive leaf drop, this is a sign that there’s something wrong with the tree.
Citrus trees shed leaves throughout the year to replace old leaves with new ones. Leaves can remain on a citrus tree for as long as three years depending on plant health and the surrounding environment.
It’s common for some citrus plants to have a bigger shed in the fall and a surge of regrowth in the spring. Winter temperatures are usually too low to regrow the new leaves until the spring flush.
This state of semi-dormancy is nothing to worry about as long as your plant isn’t dropping an excessive number of leaves or fruits.
If this is happening, it’s a sign that your plant is under stress. This can be stopped through proper care during the winter months.
What Should You Do with Citrus Trees in the Winter?
Potted citrus trees should be brought into a protected area during the winter to prevent any seasonal damage. Outdoor citrus trees will fare well in temperate climates but should be protected from any potential frost or low temperatures. Wrapping the trunk of outdoor citrus trees in cardboard will insulate them.
Evergreen trees, including citrus trees, thrive in warm and temperate climates. They can handle some colder temperatures but do best in the USDA hardiness zones 9 to 11.
Outside of these areas, it’s best to grow citrus trees in a pot so they can be moved to a protected area during the winter months.
A couple of weeks before the first frost, it’s important to start acclimating the plant to indoor conditions to avoid a sudden temperature shock. Place your plant in a shaded area before bringing it inside to reduce the stress to the plant. The same goes to acclimate back to the outdoors, just in the opposite order. This process can take a few weeks.
Once inside, it’s important to make sure your plant gets enough light and water. Because citrus trees keep their leaves year-round, they need adequate sunlight to keep making food. The best placement for indoor citrus trees is by a southern-facing window as this will provide the most light.
These plants need at least eight hours of bright sunlight, even during the winter months. Make sure to evenly water the soil until it is damp and not soggy. This will help keep your plant healthy and prevent any leaf drop.
However, if your citrus tree is outside, there are steps you can take to properly care for the plant throughout the winter.
Outdoor citrus trees should be watered weekly to make sure they can deal with any damaging cold conditions. Cardboard can also be used as insulation against frost by wrapping it in layers around the trunk.
It’s important to not prune your citrus tree until after the final frost of the season. Like other trees, citrus trees use a lot of energy to survive the winter. By pruning, you’re wounding the tree and it will have a hard time both dealing with the cold and healing wounds. Wait until after the last frost, or early spring before doing any pruning.
Reasons Why Citrus Trees Lose Their Leaves
If your citrus tree is losing excessive leaves, then there might be an issue with its growing conditions. While losing some leaves is normal, excessive leaf drop can happen whenever the citrus tree is stressed due to:
- Lack of nutrients
- Excessive fertilization
- Environmental stressors
One of the main reasons for citrus trees to lose leaves is improper care, whether you’re aware of it or not. A lack of proper nutrients such as magnesium, iron, nitrogen, zinc, or manganese can lead to weakened leaves.
Yellow leaves or ones that are thinner than usual are a sign of nutrient deficiency. A soil test can also check for any insufficient nutrients for your citrus tree.
Solutions such as Epsom salt or iron chelates can be used to restore the proper amount of nutrients to keep your plant’s leaves healthy.
Too much fertilization around the tree’s base can also lead to damage and poor drainage. This causes salt to accumulate on the leaves and eventually leaf drop. Proper fertilization will prevent this.
Environmental stressors are another reason why citrus trees lose their leaves. Sudden temperature changes will cause stress to your plant and can cause leaf drop as a result.
This is more likely to occur in the winter when a plant has to acclimate to a new environment. Allowing the plant to adjust to lower temperatures before bringing it inside will stop excessive leaf drop.
Additionally, the indoor atmosphere can be too dry for the plant to thrive. This can be counteracted by misting the tree with water and keeping it away from radiators and other heat sources (I had this problem once with my Meyer lemon tree—once I moved it in a different room from the central heat, it stopped losing leaves).
Low light levels also cause leaf drop and for the younger shoots to dry instead of flourish. Putting the citrus tree in bright light, consistent temperatures, and keeping it moist will keep it healthy and prevent leaf drop.
As far as pests, one of the most common is armored scale insects that can cause damage to your citrus tree. Severe attacks can weaken the plant and result in leaf drop. Natural predators or organic insecticides can be used to fend off these pests and prevent leaves from falling.
Another insect that can cause damage is the Asian citrus psyllid which feeds on citrus leaves. These creatures can infect trees with citrus greening disease, which can be fatal for citrus plants.
Finally, fungal diseases can cause citrus trees to lose their leaves. Root rot affects the root system of trees and causes the leaves to yellow or drop. This infection is a result of a fungus that builds up when the trunk remains wet, which is typically due to overwatering or poor drainage and can be prevented with improved watering techniques.
If you are interested in learning more about how to winterize your citrus tree to protect it from harsh conditions and leaf drop, check out this video by ehowhome!