Lemon trees have lush deep green thick leaves that naturally bear a lemon aroma.
Causes for Lemon tree leaves turning yellow include overwatering, underwatering, lack of fertilizer, temperature fluctuations, lack of sunlight, and spider mites.
Outdoor Lemon Tree Leaves Turning Yellow
Being outdoors, lemon trees fixed into the ground need you to make conditions as best for growth as possible.
Unfortunately, these lemon tree leaves are likely to turn yellow at some point in time when conditions change too much.
Here are situations that cause yellow lemon tree leaves.
More water than required will negatively impact any plant or tree in the same way.
Excessive water around the roots will cut off the air supply to the roots, stopping many reactions from occurring. Also, waterlogged soil can harm the population of beneficial microorganisms that improve soil quality.
Originating from warmer climates and regions, lemon trees do not like colder regions that experience long rainy periods.
What to Do?
Watering is a sensitive matter when it comes to lemon trees. These trees like water but not sitting in overly wet soil. Large amounts of water will result in lemon tree leaves turning yellow.
- Automatically reduce or stop watering during winter. It is an advantage to know how much cold lemon trees tolerate.
- Always feel the soil prior to watering. Avoid watering if the soil is wet, water if the soil is relatively dry. Feeling up to a depth of 4 inches should help decide the soil moisture.
- If you are experiencing rain, make sure to stop watering or make sure that the soil is dry before you do so.
- Well-draining soil makes all the difference. Soil with high quantities of clay will trap water and contribute to the accumulation of water to form puddles.
- If using pots for lemon trees, make enough drainage holes at the bottom. Also, keep an eye on and drain the tray when it is full of water.
- Chances are your soil is watery because of too much watering. Adjust your watering efforts by extending the period between watering sessions.
It works both ways, just as overwatering can cause yellow leaves, so can underwatering!
You can differentiate between underwatering and overwatering since yellowing due to underwatering usually occurs with shriveling of leaves.
If your lemon tree leaves are yellow due to lack of water, find out how much water do lemon trees need?
There are three main reasons for the lack of water in lemon trees:
- Not enough water is given during watering.
- Extremely dry air which reduces lemon tree leaf moisture.
- Very high temperatures will increase evaporation from leaves.
Keeping a tab on all of these factors will help to reduce the loss of water from your plant.
What to Do?
Keeping the environment cool and not dry will be helpful to keep your lemon tree from losing too much moisture.
- When watering, water your lemon tree very generously! The water should soak the soil thoroughly.
- Try to keep the air humid enough. If your house lacks this, try an air humidifier. You can use a water sprayer and mist the leaves a few times a day if necessary.
- Temperatures can be reduced indoors with air conditioning devices. Outdoor temperatures can be managed by providing your lemon tree with shade.
#3- Lack/Excess of Fertilizer
Fertilizer helps lemon trees grow since they are naturally heavy feeders. However, too much/little of this material is a danger to your tree!
Excessive or sparse amounts of unnecessary fertilizer can initiate the yellowing of lemon tree leaves.
Yellowing of leaves due to lack of fertilizer is also characterized by yellow leaves with green veins, otherwise known as Chlorosis.
What to Do?
You can’t mistake green veins (chlorosis) with anything else. Immediately scale back fertilizer use.
- Stick to a monthly application of fertilizer formulated for citrus trees as it works best on lemon trees.
- Use the fertilizer at the right time, spring and summer are the most appropriate times to apply fertilizer.
- Watering well can help fertilizer dissolve and be taken up better by the roots of your lemon tree.
Indoor Lemon Tree Leaves Turning Yellow
Plants aren’t regularly grown indoors unless they perfectly fit into the indoor atmosphere.
When it comes to keeping your lemon tree housed with you, the environment has to be doctored to suit lemon trees. Failure to do so may result in yellow leaves or worse!
#4- Temperature Fluctuations
Lemon trees are not accustomed to cold and grow best in hot climates such as those present in USDA Zones 9 to 11. When temperatures drop to 28℉ or -2 ℃, lemon trees need protection or else should be brought indoors.
But, upon bringing your lemon tree indoors for winter you may notice the yellowing of leaves. This is mostly because the lemon tree is switching from colder temperatures outdoors to warmer temperatures indoors.
It is expected and there is not much else you can do but just wait. It happens because the lemon tree is trying to get used to the new environment and temperatures.
As a result, the tree will experience a bit of stress, this is normal.
What to Do?
If you have just moved a lemon tree indoors and start witnessing leaves turning yellow or even some lemon tree leaves falling off, don’t panic!
There’s one important thing to do when your lemon tree is transitioning from an outdoor to an indoor tree (albeit short-term!)
That is to provide the best care and adjust to the requirements of that moment.
#5- Lack of Sunlight
There’s more than one problem lemon trees encounter when being moved indoors for short intervals or prolonged time periods. Sunlight is one such problem.
Lemon trees kept indoors will show yellowing leaves due to lack of sunlight. This is serious since yellow leaves cannot carry out photosynthesis to produce energy. Hence, the tree cannot grow or bear any flowers and fruits.
Lemon trees need 6 hours of sunlight, 8+ hours is most ideal. Sunlight is a core ingredient in photosynthesis.
Anything less than the minimum will not support growth and lemon production.
What to Do?
You must move your potted lemon tree to a position that receives more sunlight. Doing this can even save leaves that are only marginally yellow. How do you know which spot is the best one for your lemon trees?
Well, too much sun is no good either. The best place to plant a lemon tree outdoors gives ideas about where to place them indoors.
The best location indoors should be where it receives both shade as well as sunlight.
Study the sun patterns in your house. You can either place the pot on a window, near a glass door, or in a room that receives good sun. The choice is yours.
But, what should you do when you don’t get any good light? Using a grow light, you can ensure your indoor lemon tree gets light wherever it is.
Thus, you can prevent your lemon tree’s leaves from turning yellow.
#6- Spider Mites
Have you recently noticed very tiny creatures that are causing small yellow spots on your lemon tree leaves? Chances are high that these are in fact the work of spider mites!
Spider mites are small insects that feed off lemon tree leaves. Their prevalence in indoor plants is high because they prefer dry conditions with less air circulation in play.
If these conditions sound familiar it’s probably because they are a common setup in an indoor scenario.
Failure to stop spider mites will result in lemon leaves that are completely yellow. Even though this is a frightening thought, one even more frightening is of the pests spreading! Your entire tree can be damaged to the point of no more growth or death.
What to Do?
Getting rid of the spider mite pests is the goal. Doing it without the need for heavy-duty insecticides is possible if you use the right techniques.
The simplest way to eliminate and prevent spider mites is by making conditions incompatible for their growth and multiplication.
This means making your plant and the area around it less dry, you can do this with the following options:
- Interval spraying of water on the leaves.
- More frequency but light watering routines.
- Cleaning the leaves of your lemon trees with soapy water.
Yellowing of lemon tree leaves is not something a gardener looks forward to as there can be many reasons for it happening.
Sadly, there might not be enough time to pinpoint which factor is causing it until it is too late.
To help you, we have a list of the most likely reasons for lemon tree leaves turning yellow suddenly:
- Lack/Excess of Fertilizer
- Temperature Fluctuations
- Lack of Sunlight
- Pests- Spider Mites
The solution is simple, revert conditions back to the ones most appropriate for lemon trees. Eliminate the excess amount or provide what it is deficient in.
Wondering how long till my lemon tree bears fruit?
Once leaves turn completely yellow on a lemon tree you cannot reverse it. This is because chlorophyll is responsible for a leaf’s green color. When chlorophyll completely leaves a leaf, it cannot come back.
You don’t have to remove yellow leaves from lemon trees. Eventually, they naturally fall off the tree. However, if you want to make your lemon tree look presentable and save yourself from cleaning up later, you can go ahead and remove the yellow leaves. It could actually do good to your lemon tree.