Lemon trees in pots can suffer from problems if they are not fertilized appropriately, from under or overwatering, a lack of sun or pest and fungal attack. They need the perfect balance of sun, water and nutrients to grow lots of healthy green leaves and loads of lemons. Treating pest and fungal problems is essential to keep a lemon tree growing well in a pot.
This article will explore the top 11 problems with lemon trees in pots and how to solve each of them. Have a look through the list to see if any of these are affecting your tree.
1. Yellow leaves
Yellow leaves are a common problem for potted lemon trees. The most common cause is a lack of nitrogen. Nitrogen is needed by the plant and leaves to develop chlorophyll which allows the plant to produce their own food and grow bright green leaves.
Make sure potted lemon trees are fed with pelleted chicken manure at the start of every season. This will replace the nitrogen used up and make sure the tree has enough to add new, healthy growth. You could also use a specialty fertilizer which will contain all of the nutrients your tree needs, including nitogen.
Another cause of yellowing leaves is a lack of water. Leaves will often turn yellow on the edges first which will then extend across the whole leaf. Deep water the plant across the whole surface of the soil until water drips through the drainage holes.
Water the plant with a dose of seaweed solution to help the plant to recover quickly and support healthy root growth.
2. Green veins and yellow leaves
Lemon tree leaves with green veins while the rest of the leaf is yellow is a sign of iron deficiency. This will usually start on the youngest leaves first and is common in potted lemon trees that are not fertilized frequently.
Treat this problem by giving the tree a diluted solution of iron chelates. Iron chelates can be bought in powder or liquid form. Do this each spring to prevent this problem. You can also feed the plant with citrus food throughout the year to replace the iron instead.
2. Brown leaves
Brown leaves can occur on potted lemon trees due to sunburn or a lack of water. New leaves can be burnt by the harsh summer sun. Lemon tree leaves can also burn quickly if the plant has been moved from shade into the hot sun too quickly.
It is ideal for lemon trees to get at least 6 hours of sunlight. If your tree has been in shade, gradually move it out into a sunny position to allow it to adjust to the intensity of the sun to avoid sunburn.
Brown leaves on potted lemon trees can also be caused by a lack of water. Potted lemon trees will need to be watered more regularly than those in the ground. Check the soil and water up to 2-3 times per week in summer. Shade the pot by surrounding it with smaller pots to stop it drying out so fast.
3. Drooping leaves
Drooping leaves on potted lemon trees is a common problem and is caused by a lack of water. A hot summer day can cause the leaves to droop in a few hours. The soil will feel dry at least 2 inches down.
Water the tree at the end of the day deeply and thoroughly with a hose. You can prevent this problem by watering the tree the night or morning before a hot day. This will make sure the soil is moist before the weather heats up. Surround the tree with bark mulch to stop the water evaporating too quickly.
4. Fungal growth
Fungus can grow on the leaves and can look gray, black or white. Sooty mold is most common and will look like a gray covering on the leaves. It is caused when excess moisture sits on the leaves. This can happen if the tree is watered from the top or if the weather is hot, humid and rainy.
It is best to prevent this problem by watering at the base of the tree instead of on the leaves. Keep the tree well trimmed and make sure it has good air movement. You can trim off the affected areas so the problem doesn’t spread, and this will help to avoid using fungal sprays to treat the problem.
5. Slow growth
Many people notice that lemon trees can slow their growth when grown in pots. This can be due to a lack of nutrients, water or poor potting soil. To get the fastest growth possible, choose a large pot to give the tree space to grow.
Choose a top quality potting soil that contains a slow release fertilizer and lots of organic matter for good drainage. Place the tree in a position that gets at least 6 hours of sun and water it regularly. Fertilise at the start of each season with a citrus fertilizer or pelleted chicken manure. This will help your lemon tree grow fast.
6. Dropping flowers
Potted lemon trees can drop flowers and produce less fruit. Lemon trees can drop flowers if they are not being pollinated. Place your potted lemon tree in an open area where they can be pollinated by insects or the wind. For indoor potted lemon trees, take a small paintbrush and move pollen from one flower to another to help with pollination. This will help to stop them from dropping flowers before they form fruit.
7. Not growing flowers or fruit
If your lemon tree does not grow flowers or fruit at all it could be too young. Lemon trees will usually start producing flowers and fruit in their third year so if you have a small tree you may need to wait.
If you have an older tree and no flowers, add a flower and fruit promoting fertilizer this will give the tree more potassium and phosphorus. This promotes flowering by decreasing the nitrogen to potassium to phosphorus ratio.
8. Fruit drop
Fruit dropping from potted lemon trees before they mature can be caused by a lack of water or sudden temperature changes. A rapid change in temperature or stress on the tree can cause it to drop its fruit.
If you see a very hot day coming, water the tree well the night before and protect it from the afternoon sun. This can help to prevent it drying out quickly and dropping fruit.
9. Pest attack
Lemon trees in pots can be attacked by a variety of pests that can affect their growth and fruit production. Check out the most common pests affected potted lemon trees below.
Aphids
Aphids are a common pest that can attack lemon trees in pots. They are a small, green bug that sucks the sap from the stem and the leaves. Aphids can increase in numbers quickly so squirt them off with your hose or treat them with Neem oil.
Scale
Scale bugs will sit where the leaf joins the stem and will suck sap from the lemon tree. This will damage new growth and the leaves attached. Scale will form a hard coating over their body and attack themselves tightly to the stem.
To remove them before they have attacked, squirt them off with your hose or wash the stems down with some soapy water. Apply Neem oil to the bugs and the leaf areas affected. Repeat this again in 1-2 weeks if the bugs are still there. It can take multiple applications to treat this problem.
Bronze Orange Bugs
Bronze Orange Bugs (or stink bugs) are sap suckers that will attack new growth on your lemon tree. They can reproduce rapidly in spring and summer and damage the tree quickly. To remove these bugs, squirt them off with a hose, shake them into a bucket of soapy water or treat them with pest oil.
Always wear eye protection and gloves as these bugs excrete a sticky, smelly substance that can irritate eyes and skin.
10. Dropping Leaves
Lemon trees that drop leaves are stressed and might be suffering from a variety of problems. Underwatering can lead to dry soil and drooping leaves, while overwatering can cause root rot, which prevents the uptake of water.
Insufficient light and low humidity can also cause leaves to drop. To fix this issue, make sure to water your lemon trees adequately, provide them with enough sunlight, and make sure the pot has adequate drainage so the roots do not sit in water and rot.
11. Root Rot
Root rot is a fungal disease that can affect potted lemon trees, especially if they are overwatered. The disease can cause the roots to rot and prevent the uptake of water and nutrients, leading to stunted growth and yellowing leaves.
To prevent root rot, make sure to water your lemon trees adequately, provide them with good drainage, and avoid overwatering. If your trees are already infected, you might need to repot them and treat them with a fungicide.
How to Keep Lemon Trees Healthy in Pots
Here are the key factors for keeping your lemon trees happy and healthy in a pot.
1. Soil and pots
Choose good quality soil that drains well and a large pot. Good quality potting soil will contain a slow release fertilizer to feed the tree for the first 3 months. A large pot will stay moist for longer and prevent the tree drying out. Choosing the right soil is critical for the health of your lemon tree in a pot. The soil should be well-draining, with a pH between 5.5 and 6.5. A good potting mix for lemon trees should contain a mixture of peat moss, perlite, and vermiculite. Avoid using garden soil, as it can become compacted and prevent proper drainage.
2. Position
Always put a potted lemon tree in a bright sunny position that gets at least 6 hours of sunlight. Lemon trees require plenty of sunlight to produce healthy fruit.
Lemon trees should be kept in a location with a temperature between 60 and 70 degrees Fahrenheit. They can tolerate temperatures as low as 50 degrees Fahrenheit, but anything below that can cause damage to the tree.
3. Watering
Potted lemon trees will need regular water and more than those in the ground. In summer you may need to water every 2-3 days and 1-2 times per week in spring and fall. Larger pots will stay moist for longer but small pots can dry out quickly.
Check the soil with your finger and if it is dry 2 inches down, water it well. Look out for drooping leaves and water it deeply at the end of the day if this occurs.
Avoid getting water on the leaves and only water at the root base. This will avoid getting the leaves wet and causing fungal growth.
4. Fertilizer
Water potted lemon trees regularly to keep them healthy. Give them a handful of pelleted chicken manure at the start of each season, 4 times per year. Give them some trace elements and iron chelates at the start of spring to prepare the tree for fruiting over the summer.
Alternatively, give the tree citrus food in spring and again in summer. This will provide the trace elements and iron the tree needs to grow healthy stems, leaves and fruit.
When fertilizing your lemon tree, make sure to follow the manufacturer’s instructions and use the appropriate amount of fertilizer. Over-fertilizing can damage the tree and lead to nutrient burn. Under-fertilizing can result in stunted growth and poor fruit production
5. Preventing and Treating Pests and Diseases
Lemon trees in pots are more susceptible to pests and diseases than those grown in the ground. To prevent and treat problems, it is important to maintain good garden hygiene and keep the tree healthy. Regularly inspect the tree for signs of pests or disease, such as yellowing leaves, leaf drop, or spots on the leaves. If you notice any problems, treat them immediately with an organic insecticide or fungicide.
6. Regular Pruning
Pruning is essential for maintaining a healthy lemon tree in a pot. Regular pruning helps to keep the tree’s shape and size under control, and it also promotes healthy growth. You should prune your lemon tree in the late winter or early spring, before new growth starts.
When pruning your lemon tree, make sure to remove any dead, damaged, or diseased branches. Also, remove any suckers or water sprouts that grow from the base of the tree or the trunk. Finally, thin out any crossing branches to improve air circulation and light penetration.
7. Periodic Repotting
Periodic repotting is essential for maintaining healthy lemon trees in pots. Lemon trees need enough space to grow and develop a healthy root system. Over time, the potting soil can become compacted and depleted of nutrients, which can lead to poor growth and fruit production.
You should repot your lemon tree every two to three years, or when the roots start to outgrow the pot. When repotting, choose a pot that is one size larger than the current pot, and use a well-draining potting mix. Also, make sure to prune any damaged or diseased roots before repotting.
Problems with Lemon Trees in Pots | Summary
Lemon trees in pots need lots of care and are totally dependent on you to give them the nutrients they need. Common problems are caused by a lack of nutrients that can be prevented by feeding them regularly. Always water your tree regularly during the summer and you will be rewarded with lots of flowers and fruit.
Frequently Asked Questions
What are some common pests that affect lemon trees in pots and how can they be treated?
Common pests that affect lemon trees in pots include spider mites, aphids, and scale insects. To treat these pests, you can use insecticidal soap or neem oil. Apply the treatment according to the instructions on the label, making sure to cover the entire plant, including the undersides of the leaves. Repeat the treatment as needed until the infestation is under control.
What are the signs of overwatering a lemon tree in a pot and how can it be fixed?
Signs of overwatering a lemon tree in a pot include yellowing leaves, wilting, and root rot. To fix overwatering, allow the soil to dry out before watering again. You may need to repot the tree in fresh, well-draining soil to prevent further damage.
What are some common diseases that affect lemon trees in pots and how can they be prevented?
Common diseases that affect lemon trees in pots include root rot, citrus canker, and powdery mildew. To prevent these diseases, make sure the soil is well-draining and avoid overwatering. Keep the tree well-pruned and remove any diseased or dead branches. You can also use a fungicide or bactericide treatment as a preventative measure.
What is the best fertilizer for lemon trees in pots and how often should it be applied?
The best fertilizer for lemon trees in pots is a balanced, slow-release fertilizer that contains nitrogen, phosphorus, and potassium. Apply the fertilizer according to the instructions on the label, usually once every 6-8 weeks during the growing season.
What are the best pots for growing lemon trees and what size should they be?
The best pots for growing lemon trees are large, sturdy containers with good drainage. The size of the pot will depend on the size of the tree, but a good rule of thumb is to choose a pot that is at least twice the size of the root ball.
How can you prevent leaf curl on a lemon tree in a pot?
Leaf curl on a lemon tree in a pot can be prevented by ensuring the tree is well-watered and fertilized. Avoid overwatering and make sure the soil is well-draining. Keep the tree well-pruned and remove any diseased or dead branches. You can also use a copper fungicide treatment as a preventative measure.
I am an accredited practicing dietitian, experienced gardener and a dedicated cook. I love writing and sharing my experience so you can learn from my successes and mistakes.