I live in Riverside County California, which is pretty famous for its orange tree boom in the 90s we even have a historic state park miles from my home. So I’ve seen my fair share of orange trees.
Orange trees not only give us tasty fruit, but also dazzle in the garden. Unfortunately, they have their fair share of problems. And leaf curl is one of them.
When you notice your orange tree leaves curling, start to treat them at once. Because citrus leaf curl drastically affects both the quality and quantity of oranges if not treated soon.
Pest attacks. Fungal and Bacterial diseases, Nutrition deficiency, Moisture stress, and Environmental conditions are the reasons that cause the orange leaves to curl.
In this article, I have discussed the problems and solutions of orange leaf curl in detail so that you can treat them in the easiest ways.
How To Treat Orange Leaf Curl?
1. Pests on Orange Tree
There are many pests including aphids, spider mites, citrus leaf miners, citrus psyllid scales, and mealybugs that are the reason behind orange leaves curling up. All these insects feed on the leaf sap and take up all the nutrients. As a result, leaves start to curl.
When you see curled leaves on your citrus trees, check for these pests. Look for them on the underside of the leaves. If you see tunnels on the leaf surface then it’s the leaf miners. If you see small webs then it’s the spider mites. And if you see sticky substances on the leaf then it’s the aphids. But don’t forget that these pests can also attack your orange trees combinedly.
Control Measure
You need to get rid of these insects very quickly before they start damaging the fruits. But if you choose just any kind of insecticide, it can harm the oranges and make them inedible. Get the best and safest insecticide for your orange tree (our pick: Monterey organic Garden Insect Spray)
Apply horticultural oil, insecticidal soap, or neem oil to your orange tree for organic control. The recipes can be made very easily at home.
#Recipe1:-Insecticidal Soap Recipe
Ingredients:
- 500 ml of any cooking oil
- 2 tablespoons of liquid dish soap
Steps:
- Add the oil and liquid dish soap together
- Mix thoroughly
- Store this mixture in a bottle
- Add 1 tablespoon of this mixture to one liter of water
- Spray directly into both sides of the leaves and on the bark surface of your orange tree
#Recipe 2:- Neem Oil Recipe
- Mix 3 tablespoons of neem oil in 3 liters of water
- Then pour it into the sprayer
- Spray it twice a week on your Orange trees
- You can also spray it regularly as a preventive measure
Note: Before spraying these homemade solutions try on a small area first to see if it suits your orange tree. If the leaf burns then add some water to dilute the solution and try again on a small leaf. If still the leaf burns then it’s better to stop using that particular recipe for your orange.
Preventive Measure
Introduce predatory insects to your garden. These insects such as ladybugs, wasps, and lace wigs will prey on the harmful insects without damaging the orange trees.
Avoid applying too much nitrogenous fertilizer. Because nitrogen helps the vegetative growth of the tree and this invites many insects including aphids and whiteflies.
2. Disease of Orange
Bacterial and fungal diseases cause the orange leaves to curl inward. In the case of bacterial disease, the leaves get black spots on the bottom and start spreading to the top. As the disease progresses, the leaves start folding and wilting. Eventually, they drop off from the orange tree.
On the other hand, fungal diseases show a grey mold on the leaf surface. The leaves start to discolor and curl. These symptoms are not only for oranges. They can appear on any kind of citrus tree including lemon trees, key lime trees, etc.
Control Measure
You can treat the citrus leaf curl with a proper fungicide. But before choosing one, be sure it’s not going to toxify the fruits. Pick the best fungicide for your orange tree that’s safe and non-toxic for us (Our Pick: Bonide Copper Fungicide).
Treatment of these curled orange leaves can be done by some homemade approaches. The recipes for homemade leaf curl spray are given below:
#Recipe 1:- Homemade Leaf Curl Spray
Ingredients:
- 1 gallon of water
- 60 ml of copper sulfate
- 10 tablespoons of hydrated lime (Calcium hydroxide)
Steps:
- Add water and hydrated lime to a plastic bucket.
- Do not use any metal buckets.
- Because the ingredients react with metal.
- Stir the mixture slowly with a plastic spoon(Avoid metal spoons)
- Start adding the copper sulfate into the container and continue to stir.
- You have to keep stirring because the hydrated lime will settle down very quickly.
- Put the mixture into the sprayer.
- Shake the mixture very well before spraying.
- Spray on the affected leaves of your orange tree.
- Wash the sprayer thoroughly after spraying because this mixture is very corrosive.
- Don’t store this mixture for future use. Prepare a new solution every time.
Recipe 2:-Baking Soda Spray Recipe
Ingredients:
- 5 teaspoons of baking soda
- 2 teaspoons of dishwashing liquid
- 2 teaspoons of any cooking oil
- 5 liter of water
Steps:
- Add baking soda and cooking oil to a mixing bowl
- Then add the liquid soap
- Mix with water and stir slowly
- Now pour it into the sprayer
- Spray on your orange tree up to twice a week
- Continue to spray until the infection is stopped
Preventive Measure
Fungal and bacterial diseases easily infect through open wounds. So, while pruning your orange tree, make sure you are not injuring them. Also, don’t overwater the tree. Because overwatering will cause many fungal diseases Apply the homemade leaf curl spray at regular intervals to prevent fungal attacks (the recipe is given above).
3. Citrus Water Stress
Water stress is another obvious reason why the orange leaves are turning yellow and curling inwards. When the oranges are underwatered, not only the leaves but also the flowers and fruits are harshly affected. They drop off from the tree prematurely.
On the other hand, oranges don’t like to be overwatered too, especially the potted ones. Because of overwatering, the leaves start curling and wilting.
Control Measure
The amount of water is not fixed. Because it depends on the variety, the weather condition, and the size of the orange tree. If the tree is mature and tall it will obviously need more water than an immature tree.
To save yourself from those calculations and confusion of watering, you can get a moisture meter that will tell exactly how much to water (Our pick: Atree Soil Soil Tester Kits with Moisture, Light, and PH Test for Garden).
Since oranges don’t like wet soil make sure the drainage is very good. Water when the topsoil has dried.
4. Weather Effect On Orange Trees
The extreme variations in temperature can cause the orange leaves to curl. In too much heat the leaves become dehydrated and start curling to save up moisture in them. Potted oranges are also very much affected by sunburn.
Cold weather also damages and curls the leaves. The leaves become brittle and start falling off from the orange tree.
Control Measure
We cannot change the temperature but we can balance the effect of it. During dry spells feed the tree enough water and provide some shade from the scorching sun.
Apply mulch around your citrus trees so that during drying your orange tree can absorb some additional water. But be sure to keep the mulches several inches away from the tree roots.
On the other hand, during cold snaps make sure they are getting as much sunlight as possible. Cover them with plastic sheets during the night when the temperature is freezing.
5. Nutrient Deficiency
Your orange trees can start curling and turning yellow because of iron and potassium deficiency. The oranges like a pH between the 6-7 range. When the soil pH is too high these deficiency occurs. Oranges need an extra dose of balanced fertilizer before the fruiting period.
Control Measure
Feed your tree with a good well-balanced orange fertilizer with high content of potassium and iron(our pick: Miracle-Gro Citrus, Avocado, & Mango Food). Make sure while fertilizing you are not feeding an excess amount of nitrogen.
To fix the leaf curl problem naturally, apply some coffee grounds to the soil. It will work as an organic potassium fertilizer. Also, the coffee grounds will release some amount of nitrogen and phosphorus too.
Here is a homemade fertilizer recipe that you can make from scratch.
#Recipe 1:- Homemade Potassium Fertilizer
Ingredients:
- 5 banana peel
- 5 eggshells
- 4 tablespoons of Epsom salt
- 100 ml of water
Steps:
- Dry the banana peels
- Grind the banana peels, eggshells, and Epsom salt together in a food blender.
- Pour water on this powder mixture
- shake very well
- pour it into your orange tree roots.
Conclusion
Orange trees are a very fun addition to the garden. They are very hardy so they won’t take up much of your time. But orange tree leaves suffer from curling very often. This is when your intervention is needed.
Always keep your oranges away from pests and diseases. And to get juicy fruits from the tree, keep feeding it good quality fertilizers at the right time.
I hope the contents of this writing helped you solve the problem with your orange tree. There are many varieties of oranges such as Naval orange, Blood orange, etc. Doesn’t matter what type of orange tree you have planted, the treatments are the same. You can try these control measures for other citrus trees also.