Suppose you decide to start to grow a lemon tree but are confronted with a problem quite early on in the form of brown lemon leaves. You might start looking for solutions as to why are lemon tree leaves turning brown.
Lemon tree leaves turn brown due to high temperatures, frost, underwatering, salt build-up, and pests/diseases.
Environmental Reasons For Lemon Leaf Browning
Some factors in the environment may be the cause of why your plants are browning all of a sudden.
1. Excessive Temperatures – Not Enough Humidity!
Sun is an important element if you want your lemon trees to grow properly and bear excellent lemons. But, this crucial element can easily become a damaging danger to your lemon trees when in excess.
Extremely high temperatures surpassing 100℉ may burn your lemon tree leaves. We literally mean it. The leaves will start to turn brown from the tip and along the edges.
Luckily potted lemon trees can be brought under shade or onto the patio. Ground planted trees don’t have this luxury! You will have to think of another way to help them out.
Solving the Problem of Excessive Temperatures
Adjust your watering habits when you know you are in the thick of severely hot weather. If this means watering the lemon trees with more water or more often, you should do it.
But, make sure to keep checking the soil. You would hate for the ill effects to continue due to overwatering this time!
Help out your trees by providing a water-holding mulch layer on the very top of the soil. This will be crucial in keeping the moisture in and the tree rehydrated.
Make sure to do this in summer especially if you are experiencing unexpectedly high temperatures.
Many people think that frost damage just leaves lemon leaves soft, wet, or frozen. This is not entirely true. Frost may leave citrus tree leaves discolored even brown!
Lemon trees do not weather cold or frosty temperatures that well!
Although some variants may be hardier than others, Lemon tree Winter Leaf Drop should always be expected. Especially when temperatures plummet below 28℉ (-2℃) for a mere four hours or longer.
Protecting Lemon Trees From Frost
As soon as temperatures drop below 50℉ (10℃), you should start protecting your lemon trees. Older trees may be able to withstand temperatures up to 32℉ (0℃), below which the damage will be noticeable.
If your lemon trees are less than five years old, you must protect them. You can do this by covering them or moving them out of the cold. These are several ways to ensure your lemon trees (any citrus trees for that matter) stay protected in winter:
- Water the lemon trees generously several days prior to the arrival of freezing temperatures.
- Create banks around the trunk with soil.
- Wrap the entire tree with a protective yet breathable material.
- Hold off on all pruning activities till Spring. (Newly pruned lemon trees have an increased intolerance towards frost)
Can the Lemon trees survive winter? – Read here
3. Salt Build-up
Salts act as a way for lemon trees to get their share of minerals. However, excessive amounts of salts will result in a build-up. One that may trigger acute browning of lemon leaves.
The salt build-up is an interesting cause of lemon leaf browning. We will discuss why salt build-up occurs and the ways to solve it.
Lemon trees may experience a build-up of salt due to incorrect water (hard water or contaminated water). Another cause for the build-up is excessive fertilizer application. Rainwater is best for watering lemon trees.
Tap water is usually not as pure as we may think. This water is heavily treated. Unfortunately, this involves adding high amounts of chemicals and this results in the water obtaining higher amounts of minerals.
High mineral amounts affect plants, if not sooner then definitely later! Although the water may seem fine at the moment, it isn’t. As water evaporates, it leaves the salts behind. The most detrimental of these salts are Sodium and Chlorine.
Effects of high salt quantities are most noticeable in potted lemon trees. This is because there is little soil to work with and minerals cannot be naturally cycled.
Additionally, poor drainage can push salts to the top and concentrate them in the top section of the soil.
Using irrigation water from a river or a pond? There are chances the water has been adulterated by chemical waste from nearby factories. This water could contain more than just salts, it could have Chlorine or worse!
We hope this is not the case. Flushing salts is much easier than flushing chemicals.
The Solution to Salt Accumulation
If you are looking for long-term ways to prevent salt accumulation and solve it, there are three main options:
- Flushing your soil
- Carefully use fertilizer or avoid fertilizer altogether!
- Using only soft water
A. Flushing Your Soil
Salts usually surface when all the water has evaporated and they have nothing to dissolve in. So, to get rid of them just reverse the process.
Flushing the soil helps in doing this. Take water (soft water) and pour it over the soil around your lemon tree. Make sure to pour it directly over soil that falls under the tree’s canopy. All salts on and within the soil will dissolve in the water.
This will form a solution that will easily pass through the soil and leach out. To make sure all salts are dissolved, you have to make sure to water the soil for 5 minutes.
B. Carefully Using Fertilizer or Avoiding Fertilizer Altogether!
Some fertilizers may contain unnecessary minerals that your lemon tree is better off without. One example of this is Sodium. Sodium toxicity will cause gradual yellowing, bronzing, browning, and eventual loss of foliage.
Boron is another harmful element for lemon trees. An excess of Boron will cause mottling of leaves. Severe Boron toxicity may even lead to twig dieback.
Solving Fertilizer toxicity involves carefully looking at the minerals and chemicals your fertilizer contains.
Alternatively, you can switch to a natural choice like compost. Naturally, there are never excessively high amounts of Boron in organic composts.
C. Using Only Soft Water – The solution to Chlorine in Water
Solving your hard water problem involves getting rid of most of the Chlorine content in the water. Luckily, there is a relatively easy yet time-intensive way to lower Chlorine concentration in hard water.
Pour the hard water into a bucket and leave it uncovered for 4.5 days, most of the Chlorine will evaporate!
After this time, the water will have much less Chlorine. At least not enough to harm your lemon trees.
Also, you can use reverse osmosis. This involves pushing water through special filters which remove certain minerals.
4. Pests and Their Associated Diseases
Pests and diseases may not be the leading reason why lemon tree leaves turn brown in your area. But, occasionally they may be the cause of your problems.
Small round brown spots on the surface of the lemon trees could be a sign of pests. Or disease brought about by pests. White, black, or brown spots on the underside of your lemon leaves could possibly be aphids!
Depending on your region there could be local pests and diseases that affect citrus trees such as lemon trees. So, before planting these trees it would be worthwhile to get information about any pests or diseases you may encounter.
Stopping Pest and Diseases That Cause Lemon Leaf Browning
While there may not be any way to stop pests before they arrive, controlling populations is key. To do this, you must constantly inspect your lemon trees.
Look for anything out of the ordinary or anything that wasn’t there last time. If there is anything, act on it fast!
Care-Related Reasons For Lemon Leaf Browning
Sometimes care is not properly provided to the lemon trees! These are some factors to take care of when growing lemon trees.
1. Underwatering Can Cause Lemon Tree Leaves to Brown
Browning of lemon tree leaves is a sign that temperatures are excessive (exceeding 100℉) or lack of water. But, maybe it is actually a fusion of the two. Brown leaves won’t be the only problem you face due to lack of water.
The lemons could be affected as well, leading to dry juice-less lemons. This defeats the whole reason for growing this citrus tree! Failure to provide enough water may even yield no fruits, nothing that looks like a lemon at least.
Lemon trees need moisture to produce good lemons. Both the soil and air should have enough moisture. So it may support the plant through the growth and bearing of fruits as well.
Leaves will not turn brown overnight. Instead, they start off by curling to reserve moisture. If not fixed after this happens, the leaves will then start to desiccate and turn brown completely.
The solution to Fixing Underwatered Lemon Trees
If you live in dry states in the USA like Arizona or California, you know soil can dry really fast!
Preventing your lemon trees from dehydrating in these areas can be challenging but not impossible.
The trick is to immediately water the lemon trees as soon as the top 2 to 4 inches are dry. To test the moisture content in the soil, dip your finger into the depth of your second knuckle. If it feels dry, add water.
An additional step is using mulch to retain moisture. Just an inch or two of compost/mulch on the top of the lemon tree soil is suggested. This layer will trap moisture in and at the least slow evaporation.
Apart from managing to water, there may be another cause for drying out too fast. It could be the soil to blame! Make sure to add materials that are better at holding moisture. Compost materials can help in doing this.
2. Over Fertilizing Your Lemon Trees
Lemon trees enjoy an N-P-K fertilizer with Nitrogen present in double the amount of Phosphorus and Potassium. (e.g 6-3-3).
Being too generous with your fertilizer can force your lemon trees to start showing their dislike in the form of foliage browning.
The fact that lemon trees do not go dormant in winter means they need that extra push a fertilizer provides. However incorrect fertilizer or fertilizer application could be more of a danger than an actual help!
As mentioned, excessive Sodium, Boron, Calcium, or Magnesium may lead to the development of brown edges on your lemon tree’s leaves. Correcting these situations calls for some major changes to your habits and materials.
Solutions to Stop Lemon Leaf Browning Due to Fertilizer
Be very wary of which fertilizer you use. It should not have excessively high amounts of harmful elements (Ca, Mg). It should also not alter the soil pH in a way that affects your lemon trees. Use it sparingly and avoid overuse.
You could always choose to use organic material to feed your lemon trees. There are many compost combinations that can be made to suit the needs of your lemon trees. That’s of course without the risk of harming them!
Lemon trees are an appealing addition to the garden, or adding a few more to your plot is a great idea! Because who wouldn’t mind a few extra lemons in the house?
But there is always the chance of your lemon tree leaves turning brown. Correcting this is possible but tricky as there may be several causes.
- Excessive Temperatures
- Salt Build-Up
- Over Fertilizing Your Lemon Trees
- Pests and Their Associated Diseases
You must quickly identify the reason for lemon tree leaves turning brown and fix it immediately. Failure to do so could possibly affect your tree’s lemon output! So, it’s best to be aware of such issues prior to planting if possible.
Overwatering can cause damage to a lemon tree’s roots. This will hamper its ability to function properly. So, the most obvious signs of overwatering can be yellowing or browning of leaves. Premature leaf loss will probably follow the discoloration of the leaves.
The most common signs of a dying lemon tree may be curling of leaves, change of leaf color to yellow, brown, or black, and even loss of foliage. Hence, saving your lemon tree from here will depend on what the cause is and how well it is resolved.