There was a time when our olive tree started to lose its leaves and die, and we were pressed to figure out why. To help with this, I did a bunch of research and put it together in this guide in case it may help others. Here’s what I found.
Olive trees die due to various environmental factors, such as frost damage, drought, heat stress, and soil salinity. To keep your olive trees healthy, protect them from freezing temperatures, ensure they receive adequate water, avoid exposure to excessive heat, and maintain proper soil conditions.
While olive trees can die from several factors, can dying olive trees be saved, how can we tell which issue is causing it, and how can we fix it? Let’s take a closer look.
Can Dying Olive Trees Be Saved?
Dying olive trees can be revived if you find the proper issue and apply a timely solution. However, the hard part is finding out which issue is affecting them.
A good approach is to start with the possible issues based on the symptoms and try solutions starting from the least invasive to the most invasive.
The reason why we want to start with the least invasive solution first is to minimize your olive tree’s stress. This will give it the best chance of recovering.
For example, if we’ve narrowed down the possible issues to a lack of water or excess drainage, it’s much easier on the olive tree to adjust its watering than it is to dig it up or spray it with chemicals.
By approaching solutions in this way, it makes it much easier for you to treat your olive tree, and work your way up from simple solutions to more complex ones.
How to Tell If Your Olive Tree Is Dying
|Olive Tree Symptom||Issue*|
|Wilting/Curling Leaves||Under-Watered, Heat Stress, Transplant Shock|
|Yellow Leaves||Under/Over-Watered, Transplant Shock, Lack or Excess Nutrients, Pests|
|Brown Leaves||Under-Watered, Heat/Frost Stress, Transplant Shock, Pests|
|Spotted Leaves or Fruit||Pests or Diseases|
|Dropping Leaves||Under/Over-Watered, Heat/Frost Stress, Transplant Shock, Lack or Excess Nutrients, Pests or Diseases|
|Dropping Fruit||Under/Over-Watered, Heat/Frost Stress, Transplant Shock, Lack or Excess Nutrients, Lack of Pollination, Pests or Diseases|
It’s sometimes difficult to tell if your olive tree is dying, but generally, if it has any of the above symptoms, it’s likely declining in health.
Keep in mind that these symptoms aren’t normally a cause for concern if they’re affecting less than 10-20% of the plant. For example, it’s fairly normal for 10-20% of your olive tree’s leaves to be yellow or brown. The same is true for some flower or fruit drop.
However, if more than 20% of the plant is affected, or you’re seeing other concerning signs such as pest or disease symptoms, then action is likely needed to save the plant.
Keep in mind, olive trees are evergreen fruiting plants adapted to Mediterranean climates. As a result, they keep their leaves green year-round.
So, if your olive tree is losing leaves, or has other symptoms, continue reading to see what we can do to help it.
3 Quick Steps To Save a Dying Olive Tree
If you’ve already tried finding out which issue your olive has, and you’ve gotten stuck, there’s still hope.
Here are 3 steps you can use to save your olive tree, for just about any condition.
1. Identify the Possible Issues
The first step in reviving a dying olive 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 7 most common olive tree issues.
2. Isolate the Actual Issue
Once you’ve checked the specific symptoms your olive 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 olive tree is exhibiting. This gives you the best chance to provide the right solution for it (you don’t want to repot the plant if the problem is a watering issue).
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 provide less water than to repot or transplant it. Try to save those options for last.
Continue testing the treatments you believe are most likely to fix the issue. 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 noticed 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 olive tree might have, that’s okay! That’s what I’m here for. To give you a head start, let’s explore the 7 most common reasons olive bushes die.
The Top 6 Reasons Olive Trees Die
Olive trees are hardy plants, but they have their limits. They can survive in temperatures down to about 20°F (-6°C). However, if you live in an area where temperatures regularly dip below that, you may find your olive tree suffering from frost damage.
When the temperature drops, the water inside the tree’s cells can freeze, causing the cells to rupture. This lead to leaf drop, branch dieback, and, in severe cases, even tree death.
To help your olive tree through a frosty winter, I usually wrap the trunk with insulating material like burlap, and mulch around the base to protect the roots.
If you can, consider planting the tree in a sheltered location or near a south-facing wall to protect it from harsh winds and retain some warmth.
You may know that olive trees are native to Mediterranean climates, which means they’re accustomed to dry summers and moist winters. They’re fairly drought-tolerant, but still need some water to thrive.
I’ve found that deep, infrequent watering works best for olive trees, as it encourages them to develop deep root systems. When you water, make sure to moisten the soil to a depth of about 2 feet (60 cm).
During extremely dry spells, I like to give my olive tree a good soak every 2 to 3 weeks. Remember, overwatering can lead to root rot, so be mindful of your tree’s water needs.
Only water when the first 2-4 inches of soil gets dry.
I also apply 2 inches of compost every 1-2 months and 4-12 inches of mulch every 3-6 months. These dramatically improve the soil’s water retention, richness, and nutrients (promoting 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
Olive trees are used to hot, dry climates, but when temperatures climb above 95°F (35°C) for an extended period, they can experience heat stress.
This may result in leaf scorch, reduced fruit production, and even death. To help your olive tree cope with heat stress, make sure it’s well-watered during hot spells and consider providing some afternoon shade.
Again, keeping the soil moist (similar to the moisture of a wrung-out sponge) and applying compost and mulch go a long way!
Also, consider providing 2 hours of afternoon shade when temperatures get too hot. You can use taller trees, structures, or shade sails.
Olive trees are moderately tolerant of saline soils, but if the salt levels are too high, it can interfere with the tree’s ability to take up water and nutrients, leading to poor growth and even death.
To manage soil salinity, I recommend using good-quality compost to improve soil structure and help with drainage. Also, avoid over-fertilizing, as excess fertilizer can contribute to soil salinity (more on composting and fertilizing next).
2. Improper Nutrients
Nutrient management is crucial for the health and fruit production of olive trees. When olive trees don’t have enough nutrients, they develop issues such as yellowing leaves, poor growth, and reduced fruit production. And if enough time passes, the tree can die.
Let’s take a look at how to tell if olive trees have enough nutrients and the best way to fertilize them.
Lack of Nutrients
|Nutrient Deficiency||Leaf Symptom|
|Nitrogen||Entire leaf is pale or yellow|
|Iron||Dark green veins, rest of the leaf is yellowing|
|Manganese||Broadly pale leaves, foliage color looks mottled or smeared|
Olive trees need a balanced supply of nutrients, including nitrogen, phosphorus, potassium (NPK), and micronutrients like iron, zinc, and magnesium. A deficiency in these nutrients can lead to various health problems and hinder the tree’s ability to produce fruit.
Causes of nutrient deficiency in olive trees can include:
- Degraded soil
- Imbalanced soil pH
- Sandy or poorly structured soil
To fix nutrient deficiencies, use organic matter like compost or well-rotted manure to improve soil structure and provide essential nutrients. In most cases, a 2-inch layer of compost applied around the tree’s base every 1-2 months works well.
Over-fertilizing your olive tree can lead to problems as well. Excessive nutrients, especially nitrogen, can cause the tree to focus on producing vegetative growth such as leaves at the expense of fruit production. Over-fertilization can also cause root burn and weaken the tree’s overall health.
If you think you’ve over-fertilized your olive tree, flush the soil with water to leach excess nutrients from the root zone. Run a slow stream of water around the tree for 2-3 hours to help dilute the nutrients and move them further down into the soil.
How to Fertilize Olive Trees
Olive trees can benefit from a slow-release, balanced fertilizer or compost. Avoid chemical fertilizers if possible, as they can harm the soil’s beneficial organisms and lead to long-term issues.
The ideal fertilizer for olive trees should contain a balanced mix of NPK, as well as secondary nutrients like iron, zinc, and magnesium.
To see which fertilizer I use and recommend, see my recommended fertilizer page.
Soil pH is also important for olive trees, as it affects nutrient availability.
Olive trees prefer a soil pH between 7.0 and 8.0.
To measure your soil’s pH, you can use pH strips or a pH meter. If the pH needs adjustment, use appropriate soil amendments like wood ash, biochar, or lime for acidic soil, and sand, peat moss, or coffee grounds for alkaline soil.
Recommended: Are Coffee Grounds Good For Olive Trees? (Here’s The Answer)
3. Improper Pruning
Caring for olive trees involves pruning, which is crucial for promoting new growth, improving air circulation, and shaping the tree to enhance fruit production. However, improper pruning can hinder fruiting. Follow these guidelines when pruning olive trees:
- Why pruning is important: Olive trees tend to grow densely, reducing sunlight penetration and hindering pollination. Pruning opens up the tree’s canopy, allowing sunlight and air to reach the interior branches. This promotes healthy growth and increases the tree’s fruit-bearing potential.
- Timing of pruning: The best time to prune is late winter to early spring, just before new growth starts. This enables the tree to focus its energy on producing new growth and fruit during the growing season. Avoid pruning during the hot summer months or fall, as this can stress the tree and reduce its ability to produce fruit.
- Pruning techniques: When pruning an olive tree, concentrate on removing dead, diseased, or damaged branches. Eliminate branches that cross each other or grow inward, as they reduce air circulation and sunlight penetration. Create an open, vase-like shape that enables light and air to reach the interior branches.
- Avoid over-pruning: While pruning promotes fruit production, over-pruning can stress the tree and reduce its ability to produce fruit. Do not remove more than one-third of the tree’s total growth in a single pruning session.
Olive trees, like all living things, eventually reach the end of their natural lifespan and die of old age. As they age, their ability to produce fruit decreases and they become more susceptible to disease and environmental stress.
In addition, their roots can become less efficient at absorbing nutrients from the soil, which can cause the tree to weaken and eventually die.
The average lifespan of a commercial olive tree can vary depending on several factors such as the cultivar, growing conditions, and management practices. However, in general, a commercial olive tree can produce fruit for around 35 to 50 years, after which its productivity may begin to decline significantly.
While the tree may still survive for a few more years after this point, it may not produce enough fruit to remain profitable for commercial olive growers.
For best results, follow proper pruning, watering, nutrient, and other practices in the rest of this guide.
5. Physical Damage
Olive trees can get damaged from a variety of things like harsh pruning, lawnmowers, weed whackers, or even kids and pets playing a little too close.
When an olive tree is damaged, it becomes vulnerable to diseases and pests. I’ve seen this happen in my garden when I accidentally grazed the trunk of my olive tree with a lawn mower. It wasn’t long before I noticed some fungal growth near the wound and I knew I had to act quickly to save my tree.
One way to remedy physical damage is by properly caring for the wound. Start by cleaning the damaged area with a mild solution of water and a few drops of dish soap.
Then, you can use a pruning sealer or tree wound dressing to cover the wound. This will help protect the tree from further damage and infection.
Don’t forget to keep an eye on the tree’s overall health as it recovers. And remember, prevention is key! Be mindful of your tree’s surroundings and try to avoid any potential hazards that could cause physical damage.
Now, let’s talk about transplant shock. This is a stressful event for the olive tree that can happen when you move the tree from one location to another. For example, when you’re transplanting it from a pot to the ground or vice versa.
Transplant shock can cause the tree to wilt, lose leaves, or even die if not addressed properly. It can also take up to a year for the tree to recover.
I experienced this when I moved my potted olive tree to a sunnier spot in my garden. For a while, it looked pretty sad, and I knew I had to find a solution to help it bounce back.
Here’s a summary of how to take care of an olive tree with transplant shock (much of the tips are throughout this article, but I thought I’d summarize them here for you too).
- Water: Make sure your olive tree is well-watered, but not overwatered. Remember my wrung-out sponge tip? That’s how moist the soil should be. Water when the first 2-4 inches of soil are dry and check this by pushing your finger into the soil.
- Mulch: Apply a layer of organic mulch around the base of the tree to help retain moisture and regulate soil temperature. This will also help suppress weeds and provide some extra nutrients as it breaks down.
- Fertilizer: Use a balanced fertilizer, like one with an NPK ratio of 10-10-10, to give your tree the nutrients it needs to recover. In case you’re wondering, NPK stands for nitrogen (N), phosphorus (P), and potassium (K), which are the primary nutrients plants need to grow.
- Pruning: Prune your olive tree carefully to remove any dead, damaged, or diseased branches. This will help the tree direct its energy to healthy growth and recovery.
- Protection: If you live in an area with extreme temperatures, consider using a tree wrap or burlap to protect your tree from harsh winds or sun-scald.
Now, I know we prefer natural methods, but if you’re really struggling and need a conventional solution, you could try using a root stimulator or transplanting solution that contains hormones and nutrients to help your tree establish its roots more quickly. Just be sure to follow the product instructions.
6. Pests and Diseases
Aphids are tiny, sap-sucking insects that cause olive tree leaves to curl and drop.
When aphids feed on the leaves and tender shoots, they weaken the tree and stunt its growth (and fruit production).
Additionally, they excrete a sugary substance called honeydew, which can lead to the growth of sooty mold, further damaging the tree. It’s worth noting that aphids can also transmit harmful viruses.
To prevent aphids from making a home in our olive trees, we can use a few strategies.
First, plant companion plants like marigolds, nasturtiums, or chives near your olive trees. These plants repel aphids naturally.
Second, encourage beneficial insects like ladybugs, lacewings, and hoverflies, which love feasting on aphids (pictured above). You can attract them by planting their favorite flowers, such as yarrow or dill, nearby.
Now, if aphids have already infested your olive tree, don’t worry! I’ve got you covered. One simple method is to knock them off with a strong spray of water from a hose. This is what worked for me on my lime tree, and the aphids never came back. Do this early in the day to allow leaves to dry, reducing the risk of fungal issues.
Another option is to make a homemade insecticidal soap by mixing a few drops of mild liquid soap with water. Spray it onto the affected areas, making sure to cover both the tops and bottoms of the leaves. Reapply every 4-7 days until the aphids are gone.
If these methods aren’t enough, you can consider using a conventional treatment like a neem oil spray or a store-bought insecticidal soap. Just remember to follow the manufacturer’s instructions for proper application and safety precautions.
Olive Knot Disease
Olive knot disease is caused by the bacterium Pseudomonas savastanoi, which enters the tree through wounds or natural openings (as we covered in the previous section).
I like to think of it as an unwanted guest that slips in through the cracks.
To prevent this, check how we prune our trees and avoid creating unnecessary wounds. For example, always use clean, sharp tools when pruning, and try to prune during dry weather to minimize the risk of infection.
Consider planting beneficial companion plants that attract beneficial insects to help keep the bacterial population in check.
Recommended: The Top 5 Companion Plants for Olive Trees
Verticillium wilt is a soil-borne fungal disease that affects the tree’s vascular system. It’s most commonly caused by the fungus Verticillium dahliae.
The key to preventing this disease is maintaining healthy soil, as healthy soil promotes healthy plants. Build soil fertility through methods like composting, mulching, and using cover crops. These practices not only improve soil structure but also help suppress the growth of harmful fungi.
Additionally, try rotating your olive trees with other non-susceptible crops if you have the space to reduce the risk of infection.
Bacterial diseases in olive trees can be caused by various bacteria, such as Xylella fastidiosa, which is responsible for the olive quick decline syndrome.
To tackle bacterial diseases, focus on boosting the tree’s immune system. One of my favorite permaculture tips is to use a whey spray instead of chemical sprays. Whey, a byproduct of cheese-making, is rich in beneficial bacteria that can help protect your olive trees from harmful pathogens.
Remember, healthy trees are less likely to succumb to diseases!
To give you a head start, Stefan Sobkowiak – The Permaculture Orchard has a great video on a safe, homemade, and most importantly—effective fungicide (hint: the secret ingredient is whey).
The olive fly is a common pest that can wreak havoc on your olive trees. The adult female fly lays her eggs in the olive fruit, and the larvae feed on the pulp, causing damage and reducing the yield.
To combat olive flies, I recommend using insectary plants, which attract beneficial insects that prey on olive flies. You can also use traps with a specific attractant for olive flies if the infestation is severe. Of course, there are chemical solutions available, but I always prefer the more natural approach.
Here are some companion plants that help repel olive flies:
These plants either deter olive flies with their scent or have natural insecticide properties.
Need More Help?
You can always ask us here at Couch to Homestead, but you should know the other resources available to you! Here are the resources we recommend.
- Local Cooperative Extension Services: While we do our best with these articles, sometimes knowledge from a local expert is needed! The USDA partnered with Universities to create these free agriculture extension services. Check out this list to see your local services.
- Permaculture Consultation: Need help with a bigger project? Send us a message.