Citrus trees are a genus of flowering trees and shrubs that belong to the family Rutaceae. Native to Australia and Asia, they have glossy, oval-shaped leaves and bear edible fruits including lemon, sweet orange, tangerine, grapefruit, and lime, among others. Like most plants, these trees are also susceptible to certain diseases and infections, as well as the effects of poor cultural care, any or all of which could lead to the plant’s death unless treated promptly.
Why is my citrus tree dying?
Over- or underwatering
Overwatering your citrus tree could lead to root rot because constantly waterlogged soil prevents air circulation around the roots, and the roots are therefore unable to absorb oxygen. The leaves will turn pale green or yellow and may curl or drop off. Meanwhile, rotting roots will appear brown or black and will feel mushy, as opposed to healthy roots which are firm and pale. The best way to save your plant from root rot is to repot it in a new, clean pot, using fresh soil, because the old pot and soil will be infected with pathogens.
Underwatering, on the other hand, can leave your plant dehydrated, resulting in dry, crisp leaves which will eventually fall off. Keep the roots cool and help the soil retain moisture by mulching around the base of the tree. However, make sure the mulch does not touch the tree directly, as it could introduce diseases.
Incorrect growing conditions
Citrus trees are more likely to die if their soil or their pot has inadequate drainage. Effectively, poor drainage causes overwatering, because the soil retains moisture for too long, which drowns the roots. The plant may develop dull leaves, weak branches, slow or stunted growth, and premature fruit drop. Move the tree to an elevated spot with loose or loamy soil, or plant it in a raised bed. Gravity assists the drainage of excess water from the soil while still allowing the soil to retain a degree of moisture.
Potted citrus trees should have sufficient drainage holes in the pot, and well-draining soil. If the soil retains too much water, repot the tree in new and appropriate soil. The tree should be placed in an area where it can get sunlight for at least six hours daily.
Lack of nutrients
If your citrus tree is developing yellow leaves that eventually fall off, this could be an indication of a nitrogen deficiency. If not addressed in time, this could lead to the complete loss of the tree’s leaves, and even death. Nitrogen is important for foliage growth and the overall health of trees. However, too much nitrogen could also harm the plant, because it can burn the roots.
Provide a good balance of nutrients by using a fertilizer that contains nitrogen, phosphorus and potassium at a ratio of 2:1:1. A good choice for citrus trees is a 6-3-3 fertilizer.
Pests or diseases
Root rot, which is a fungal disease, is common among citrus trees and is usually caused by overwatering. Once the roots have become compromised by the excess moisture, they are susceptible to pathogens in the soil, which attack the roots and cause the rot to spread faster throughout the plant. To have a chance at saving your tree, you need to catch the rot before it has affected the entire tree and remove its damaged and rotten roots before replanting it in fresh, sterile soil.
There are also several pests that can ravage citrus trees and suck the sap from their tissue. This will weaken the tree, resulting in discolored leaves that eventually fall off. It is easier to deal with a pest infestation in its early stages, so make a habit of checking for pests every time you water your tree, and eliminate any infestations before they become severe.
How to save a dying citrus tree
Pinpoint the possible causes or problems.
To successfully save your dying citrus tree, you will need to determine the most probable cause of its declining health. Identify the specific symptoms your tree is displaying, cross-check these with the most common problems encountered by citrus trees, and see if you can match them with any specific issue or cause. It might be useful to consult your local nursery for help in determining the cause of the problem, and for advice regarding the best solution.
Test the solutions.
After identifying the most likely solutions, start testing them. Begin with the least invasive, such as adjusting your watering schedule, and work your way up to the most invasive, such as repotting the tree. Testing each possible solution will help to determine the most effective one.
Essential tips for saving your dying citrus tree
To help your plant bounce back to optimal health, provide it with the best possible growing conditions. Give it at least one to two inches of compost every one or two months; this is one of the best sources of nutrients for your citrus tree. Also, apply fertilizer before every growing season. Citrus trees are heavy feeders and they need nutrients to thrive and bear fruit.
Check that your tree is getting the correct levels of sunlight. Citrus trees thrive in sunny areas, so placing them somewhere next to a sunny, south-facing wall will be ideal.
Can I save my citrus tree if it has lost all its leaves?
To check whether a citrus tree with no leaves can still be revived, cut off a small branch to inspect the inside. If you can see a wet, green inner surface, it means the tree is still alive and can be saved with the correct care and attention.
Citrus trees are widely cultivated for their edible fruits, which are popular in every nation worldwide. Like most plants, they are prone to diseases and the effects of poor cultural care, and in these cases may manifest symptoms such as wilting or discolored leaves and unhealthy root systems. You can save your dying citrus tree by identifying the probable cause of its declining health and then applying the available solutions, starting with the least invasive, such as adjusting your watering techniques. If this less invasive solution does not help the tree, you will need to take further measures, such as repotting it in a new pot with fresh soil and possibly even pruning the root system.
Image: istockphoto.com / Olga Ostapenko