We had a dwarf lemon tree that wasn’t doing so well, and we were afraid it was starting to die. Not sure what the issue was, we did more research and testing to find out more.
Here are the most common reasons lemon trees die (in order):
- Under or Over-Watering
- Extreme Weather (especially dry and cold weather)
- Improper Nutrients
- Transplant Shock
- Pests and Diseases
The good news is most of these issues can be fixed without much effort.
For example, under and over-watering can be avoided if you only water when the first 2 inches of soil gets dry. For nutrients, applying organic fertilizer or compost every few months provides the lemon tree with sufficient nutrients.
Don’t worry, we’ll go over each of these common causes in more detail.
But first, can lemon trees even be saved in the first place? And from there—how can we save it? Let’s take a closer look.
Can Dying Lemon Trees Be Saved?
A dying lemon tree can be saved if the issue is caught early and hasn’t done too much damage. For example, if under-watering is the issue, and the tree has only lost a few leaves, it’s reasonable to expect the tree to make a full recovery.
However, if the tree is drought stressed to the point where it lost all of its leaves, it’s up to the amount of remaining stored energy in the tree and roots to determine if it will survive and grow new leaves.
How to Tell If a Lemon Tree is Still Alive
You can tell if your lemon tree is still alive if you prune a small branch or scratch the bark and see green inside. If the branch snaps off and is dry and brown, test the bark further down the tree.
If that bark is dry and brown, check to see if the roots are green inside.
Can Lemon Trees Regrow Their Leaves?
I had a potted lemon tree that lost the majority of its leaves from frost and it grew them all back in the spring. However, catching these issues early on means less stress and a better chance of survival for your lemon tree.
Unlike apple and cherry trees, lemon trees are evergreen, so they keep their leaves year-round. If your lemon tree is losing more than 10% of its total leaves, it’s likely stressed from a condition such as improper watering or climate.
So, don’t worry too much if your lemon tree is losing some of its leaves.
For now, let’s explore the best way to save a dying lemon tree.
3 Steps To Save a Dying Lemon Tree
If you’ve already tried finding out which issue your lemon tree has, and you’ve gotten stuck, there’s still hope.
Here are 3 steps you can use to save your lemon, for just about any condition.
1. Identify the Possible Issues
The first step in reviving a dying lemon tree is to identify the possible issues. After all, the process of elimination wouldn’t work if we didn’t know which options we were eliminating!
If you haven’t seen them yet, reference the below sections for the top 6 most common lemon issues.
2. Isolate the Actual Issue
Once you’ve checked the specific symptoms your lemon has, you can now cross off potential issues from your list.
Try to get it down to 1-3 potential issues that best match the symptoms your lemon tree is showing. This gives you the best chance to provide the right solution for it. For example, you don’t want to repot the plant if the problem is a lack of water.
3. Test Solutions
Now that you have a narrowed-down list of the potential issues, it’s time to try the solutions one at a time.
Start with the least invasive solution and work your way up to the most invasive. Again, it’s much easier on the plant (and you) to simply adjust the watering than to repot or transplant it. Try to save the more stressful options for last.
Continue testing the treatments you believe are most likely to fix the issue. And hopefully, one of them sticks.
Worst case scenario, start from step 1 and make a new list of possible issues. There’s a chance you might have missed something or you notice something new the second time around.
Stay persistent! It’s easy to say, “Dumb plant, why don’t you want to live?”, but there’s always a reason why plants act the way they do. Stay the course and see if you can uncover it.
If you have no idea what issue your lemon tree might have, that’s okay! That’s what I’m here for. To give you a head start, let’s jump into the 6 most common reasons lemon trees die.
The Top 6 Reasons Why Lemon Trees Die (& Fixes)
1. Under-Watering
You can tell if your lemon tree is under-watered if you see:
- Curled Leaves
- Dried Leaves
- Brown Leaves
- Dropped Leaves
- Constantly Dry Soil
When a lemon tree has too little water for an extended period, it becomes drought-stressed and begins to show signs of decline. A common symptom is leaves starting to curl, which helps the leaves conserve moisture. If left for too long, the leaves dry, brown, and drop.
The issue of insufficient water is made worse by hot and dry weather evaporating any remaining moisture from the soil (more on weather later).
How to Water Lemon Trees
The best way to water lemon trees is to only water when the top 2-4 inches of soil is dry. You can check this by pushing a finger into the soil. The goal is to have soil moisture similar to a wrung-out sponge. This method avoids both under and over-watering.
When watering, make sure to soak the soil down to at least 2 feet deep. The reason behind this is that 90% of the tree’s roots are found at this depth. Deep watering also promotes deeper roots, allowing the tree to become more water independent in times of drought.
However, if you frequently find your lemon tree’s soil is completely dry within 24 hours, its soil needs to be amended for better water retention.
Use Compost & Mulch
Apply 2 inches of compost and 4-12 inches of mulch to promote the best water retention and fix under-watering.
Compost provides valuable nutrients and increases the water retention of the soil. For example, every 1% increase in the soil’s richness (organic matter) leads to an additional 20,000 gallons of water held per acre (source).
Mulch dramatically reduces evaporation, regulates soil temperature, and prevents soil erosion. As lemon trees evolved as understory species in forests, they’re used to plenty of mulch in the form of fallen leaves and branches. As permaculture guru Geoff Lawton says, “A forest grows from a fallen forest.”
To recap:
- Apply 2 inches of compost every 1-2 months
- Apply 4-12 inches of mulch every 3-6 months
- Keep both materials under the drip line (canopy) and at least 3 inches from the tree’s trunk to prevent mold
Compost and mulch are two of the most beneficial practices you can do, and by combining this with only watering when the soil is dry, you’re dramatically reducing the likelihood your lemon tree gets under-watered.
However, what if you feel the soil and it’s been sopping wet for days at a time?
2. Over-Watering
You can tell if your lemon tree is over-watered with symptoms such as:
- Yellow Leaves
- Green Leaves Dropping
- Root Rot (soil smelling like a swamp)
As with under-watering, use the finger test to avoid over-watering and find out when you need to water your lemon tree. If you feel the soil and it’s sopping wet, hold off on watering.
While over-watering is possible in all soil types, it’s most common in poorly draining soils or those that are sunken in the ground. This issue is compounded if the sunken soil is at the base of a hill and receives plenty of runoff.
Poor drainage is usually caused by compacted soils or those with heavy clay content. Since clay particles are much smaller than sand or silt, they easily form a tight layer that allows little to no water to pass.
Test Soil Drainage
An accurate and fairly easy method to find your soil’s drainage is by doing a percolation test.
Here’s how to do one:
- Dig a 1-foot by 1-foot hole (outside of your tree’s drip-line to avoid damaging its shallow roots)
- Place a yardstick in the hole and fill it with water
- Wait an hour and measure the rate that the water has drained
The ideal rate of drainage is 2 inches per hour.
For best results, perform 3 percolation tests in different areas of your yard to get a more complete picture of your soil’s drainage. While it can take some time, it’s helpful to know your soil types.
Naturally, if the percolation test is slower than 2 inches per hour the soil has poor drainage. Faster than 2 inches is fast drainage.
However, this is a guideline and not a rule, so don’t worry if yours is way off. The goal is to simply see if your soil’s drainage is poor or fast.
Use Compost (Avoid Mulching)
What’s interesting is that poor-draining soils and fast-draining soils have the same solution—increase the soil’s organic matter (AKA compost).
This is because compost not only breaks up the clumps of poorly draining soil but provides the ideal water retention.
If your lemon tree’s soil has poor drainage and is getting over-watered, I’d suggest applying 2 inches of compost every 1-2 months until the soil is amended. It can take some time, but the compost’s particles work their way down into the soil and break up the clumps of soil over time.
Remember to avoid using mulch until the lemon tree’s soil is draining well. Mulch makes poor drainage worse by trapping moisture and preventing evaporation.
3. Extreme Weather
The best climates to grow lemon trees are in USDA hardiness zones 9-11 (between 20ºF and 90ºF). Because lemon trees are natively from the tropics, they prefer warm, humid weather and little to no frost.
As a result, it can be challenging to grow them in drier or cooler climates. If it gets too dry or too cold, lemon trees can die in a matter of weeks or even days.
Tip: If you don’t know your USDA Hardiness zone, check out this map by the USDA. These zones show the average minimum temperature in your area and help you find the best plants to grow in your climate.
Let’s take a look at how to care for lemon trees if you don’t live in a tropical climate.
Hot & Dry Weather
While lemon trees do well in hot and humid climates, they have some difficulty growing in areas such as Arizona and New Mexico. This is typically because the lemon tree’s leaves and soil dry out quickly, causing their leaves to curl, dry, brown, and drop.
To help solve this, it’s helpful to know how lemon trees naturally keep themselves cool.
Lemon trees cool themselves by:
- Sending moisture from its roots to its leaves
- Exhaling moisture (transpiration)
You can think of transpiration similarly to how we sweat to keep ourselves cool.
So, you can successfully grow lemon trees in drier climates if you keep their soil moist (similar to a wrung-out sponge) and keep the area more humid.
Here are some best practices to grow lemon trees in hot and dry climates:
- Compost: Apply 2 inches of compost to increase water retention
- Mulch: Apply 4-12 inches of mulch to reduce evaporation and regulate soil temperature.
- Humidifier: For indoor lemon trees, place a humidifier nearby. Similarly, keep the lemon tree away from the central heat as this quickly dries out their leaves (I ran into this issue with my potted lemon tree).
- Greenhouse or Mister: For outdoor lemon trees, grow in a controlled climate such as a greenhouse or use a mister to cool the air and increase humidity. Make sure it doesn’t get too hot in the greenhouse.
- Plant Densely: You can increase humidity via transpiration by growing lemon trees near other plants. The more plants nearby, the more shade and humidity. For example, using companion plants in a food forest is great at establishing a microclimate and promoting humidity as well as increased groundwater.
Frost
On the other hand, if you live in a climate that gets light to moderate frost, lemon trees can begin to die. This is typically in USDA hardiness zones 8 and below (20ºF-25ºF).
Symptoms of frost damage for lemon trees include:
- Leaves Curling
- Leaves Dropping (Usually While Green)
While lemon trees typically can handle temperatures down to 20ºF-25ºF, I found their health declines once temperatures dip below 32ºF.
For example, when I lived in Austin, Texas, and temperatures dipped below 32ºF, my lemon tree’s leaves iced over and began losing green leaves.
Other fruit trees such as apple and cherry trees thrive in cold climates because they are deciduous (shedding their leaves in the fall) and go into a dormant state to survive the winter. These trees actually prefer some frost as it gives them “chill hours”, which helps them flower and fruit in the spring.
However, lemon trees are a tropical fruit tree and are evergreen (keeping their leaves year-round). They haven’t developed ways to survive well in temperatures of 32ºF and below. At this point, the cells inside of their leaves begin to freeze, and the tree’s health declines.
Here are some methods to help lemon trees survive (some) frost:
- South-Facing: You can plant lemon trees on the south side of your property for maximum sunlight and warmth (this is north if you live in the southern hemisphere).
- South-Facing Wall: Similarly, a south-facing wall captures and reflects more heat onto the lemon tree (again, this north if you live in the southern hemisphere).
- Cover: Wrap the lemon tree’s canopy with a bedsheet to reduce the effects of windchill and frost buildup. You can also place mulch at the base of the tree to insulate the roots and wrap the trunk with cardboard.
- Greenhouse: Greenhouses allow sunlight to warm the indoor air while blocking the outside cool air. On average, a greenhouse increases temperature by 10ºF in the winter and 20-30ºF in the summer.
- Microclimates: You can slightly adjust the temperatures your lemon tree is exposed to by establishing a microclimate. All of the above solutions are examples of microclimates, and you can also use other plants to transpire and increase humidity (reducing the effects of frost slightly).
To learn more about microclimates, check out this cool video by Gardener Scott.
4. Improper Nutrients
Excess Nutrients
Too many nutrients are often caused by fast-release chemical fertilizers as compost isn’t potent enough. When this happens, the tree’s roots can become chemically burned, causing the tree stress and leading to a decline in health.
If you believe you’ve over-fertilized your lemon tree, I suggest removing as much of the fertilizer as possible via leaching. To do this, soak your lemon tree’s soil to dilute the existing fertilizer and allow it to flow deeper into the soil (out of reach of the tree’s roots). You may have to do this at least a few times.
However, avoid leaching if your soil has poor drainage as the soil can become waterlogged. In this case, either apply generous amounts of compost and garden soil or repot the tree with fresh potting soil (for potted lemon trees).
Lack of Nutrients
| Nutrient Deficiency | Leaf Symptom |
|---|---|
| Nitrogen | Entire leaf is pale or yellow |
| Iron | Dark green veins, rest of the leaf is yellowing |
| Zinc | Yellow blotches |
| Manganese | Broadly pale leaves, foliage color looks mottled or smeared |
If you haven’t fed your lemon tree in the past several months, there’s a good chance it may be dying from a lack of nutrients.
Symptoms of a lack of nutrients depend on the deficiency.
For example, lemon trees commonly get nitrogen and iron deficiencies, showing as lightly colored or yellow leaves. This is more likely in younger lemon trees as nitrogen is the primary nutrient needed for growing a canopy.
Let’s take a look at the optimal way to prevent a lack of nutrients for your lemon tree.
The Best Way To Fertilize Lemon Trees
The 3 main nutrients for lemon trees (and all plants) are nitrogen, phosphorus, and potassium (abbreviated as NPK). Secondary nutrients such as iron, magnesium, zinc, and copper are also important and are included in most fertilizers.
However, lemon trees (and other citrus trees) prefer double the nitrogen. This is especially true for young lemon trees as nitrogen is the primary nutrient required to grow a canopy and root system.
Because of this, use a fertilizer with an NPK ratio of 2:1:1. For example, a 6-3-3 NPK fertilizer works well. Each brand has different potencies, so follow the instructions on the label for the best results.
I recommend using organic fertilizer or compost over chemical fertilizers.
While chemical fertilizers have nutrients in quantity, they often lack quality. This lack of quality means chemical fertilizers commonly contribute to dry and dead soil (AKA dirt). It does this by blocking the nutrient exchange between lemon trees and the beneficial soil life such as earthworms and mycorrhizal fungi.
Mycorrhizal fungi promote many aspects of plant life, in particular improved nutrition, better growth, stress tolerance, and disease resistance.
Department of Biology, University of Fribourg, Switzerland
Alternatively, you can use compost. For example, many gardeners are finding that compost is replacing their chemical fertilizers. I recommend applying 2 inches of compost every 1-2 months under the tree’s drip-line or canopy. Applying mulch on top of the compost goes a lot further and adds to the water retention and nutrients.
Generally, I prefer using both compost and organic fertilizers.
Either one you choose, if you’d like to see which fertilizers and compost I recommend, check out my recommended fertilizer page.
Keep in mind that while nutrients are essential, they aren’t everything.
Imbalanced Soil pH
Lemon trees prefer a soil pH of 6.0 to 7.0.
When lemon trees have an imbalanced soil pH, they develop issues such as discolored and dropping leaves. Additionally, their flowers and fruit can drop early and the tree is more likely to develop other issues.
The reason lemons (and most plants) prefer a slightly acidic soil pH is that it dissolves the nutrient solids in the soil, making them more accessible to the plant’s finer roots.
Fourteen of the seventeen essential plant nutrients are obtained from the soil. Before a nutrient can be used by plants it must be dissolved in the soil solution. Most minerals and nutrients are more soluble or available in acid soils than in neutral or slightly alkaline soils.
Donald Bickelhaupt, Instructional Support Specialist, Department of Forest and Natural Resources Management
Two good ways to test your soil’s pH are with pH strips or a meter. I prefer using a pH meter since they’re affordable and easy to use. To see which pH I recommend, check out my recommended tools page.
If you find your lemon tree’s soil is too alkaline (above 7.0), provide acidic amendments such as peat moss, lime (ground limestone), and coffee grounds.
On the other hand, if your soil is acidic (under 6.0), provide alkaline amendments such as charcoal, wood ash, and lime.
5. Transplant Shock
If your lemon tree was recently planted or repotted, and it’s starting to die, it’s likely due to transplant shock. Transplant shock occurs when a plant is exposed to a new environment and has to establish a new root system.
Avoid transplanting lemon trees unless necessary as it can take up to 1 year for recovery.
To help avoid transplant shock, I like to plant with the following steps in mind:
- Have the new ground (or pot) prepared
- Remove as much of the plant’s current topsoil as possible, without damaging the shallow roots
- Grab the base of the plant’s stem and wiggle lightly
- Using your other hand, scoop up and support the rootball
- Lightly place the plant in the new ground (or pot) and fill it in
- Make sure the soil is at the same level on the plant as before
- Apply 2 inches of compost and 4-12 inches of mulch to the top of the soil
- Water generously and add more soil as needed
6. Pests & Diseases
Aphids & Spider Mites
Aphids and spider mites are small bugs that suck the sap from underneath the lemon tree’s leaves. This loss of sugar and moisture causes the leaves to curl, discolor, and drop. Aphids also deposit honeydew, which attracts ants. On the other hand, spider mites leave behind webs.
If left unchecked, aphids and spider mites can damage the lemon tree’s health and potentially stunt its growth or kill it.
The best ways to get rid of aphids and spider mites on lemon trees is by spraying the infected leaves with water or neem oil, or releasing ladybugs (a natural predator of aphids and spider mites). Most often, a jet of water is enough to knock them off and kill them, but neem oil is a good second option.
For example, when my potted Kaffir lime tree had aphids, I found that a jet of water was sufficient to blast them off and prevent them from coming back. All I did was remove the hose nozzle and used my thumb to increase the pressure. Just keep in mind that too strong of a blast can damage the leaves.
To attract ladybugs to your garden, you can plant lemon tree companion plants such as dill, fennel, and yarrow.
Root Rot
Root rot kills off the lemon tree roots, which stresses the plant and causes symptoms such as fruit, flowers, and leaves yellowing, browning, and dropping. If not addressed, it leads to stunted growth or a dying lemon tree.
There is no chemical control available for crown and root rot in the home garden. The most important control strategy is careful water management.
Clemson University Cooperative Extension Service
You can typically tell if your lemon tree has root rot if the soil is staying sopping wet and starts smelling. Allowing the soil to dry out or repotting lemon trees with fresh potting soil are the best ways to amend this disease.
For example, I noticed my potted Kaffir lime tree had root rot as its soil smelled swampy and was staying wet for many days at a time. In this case, I repotted it with fresh potting soil, and the tree quickly recovered.
Citrus Greening
Citrus Greening disease (Candidatus Liberibacter asiaticus) is the most harmful lemon and citrus tree disease worldwide. Common symptoms include yellow leaves, spotted yellow leaves, hard or inedible fruit, dead twigs, and stunted trees.
This disease is spread by an infected insect called Asian citrus psyllid, once it feeds on the leaves, it transmits the disease to the tree. And once a tree is infected, there is no cure. The majority of citrus trees infected die within a few years.
Citrus Greening disease is currently active in California, Florida, Georgia, Louisiana, Puerto Rico, South Carolina, Texas, and the U.S. Virgin Islands. This is why it’s important not to transport citrus trees or fruit to other areas.
If you’d like more information about Citrus Greening in your area, I recommend contacting your local USDA cooperative extension office.
A Note on Pesticides, Fungicides, and Herbicides
We recently had an issue with caterpillars eating our basil plants and we were about FED UP. Every time we’d plant basil plants, the caterpillars ate it.
Fortunately, we found an organic spray at our local nursery that’s made from fermented rum. The day after spraying, we’d find dead caterpillars on the soil.
If you’d like to find out more about this organic spray, you can find it here on Amazon.
So, what’s my point here?
Even though chemical sprays and fertilizers are easy, there are often long-term costs. Namely to the plants, soil, and surrounding beneficial life.
Before using chemical sprays, weigh the pros and cons and consider trying organic or permaculture-based treatments first!
To give you a head start, Stefan Sobkowiak – The Permaculture Orchard has a great video on a safe, homemade, and more importantly—effective fungicide (hint: the secret ingredient is whey).
Also, check out how Mark Shepard uses a method called STUN (Sheer-Total-Utter-Neglect) to help his berries, fruit, and nut trees THRIVE.
Final Thoughts
We found our lemon tree was dying from over-watering. Once we started doing the finger test and only watering when the soil was dry, our lemon tree recovered. We also gave it compost and organic fertilizer (to rule out a nitrogen or iron deficiency), so that could have helped too.
It still has a few yellow leaves, but they stopped dropping and it’s moving in the right direction.
Remember, lemon trees grow best in warm climates and like plenty of water. Use the above tips to provide the best care for your lemon tree.
