6 Reasons Why Strawberry Leaves Turning Yellow and How to Fix Them

Yellowing strawberry leaves can be caused by improper planting, incorrect care, nutrient deficiency, excessive fertilizer, diseases, or pests. Don’t overlook this, as the reasons vary significantly.

This issue often troubles growers, and while sometimes a small adjustment in care or fertilization can solve it, other times, the plant may need more serious treatment.

So, it’s crucial to promptly identify and address the cause of the yellowing to promote healthy strawberry growth.

1- Inappropriate Growing Conditions

Even when still quite young, strawberry plants can turn their leaves yellow. If you plant the bushes improperly, they start drying out and turning yellow at an early stage. Consider the plot selection for these berry types; it might not be suitable.

You should avoid planting strawberries near raspberries or tulips, as this can lead to the appearance of spots and drying out of leaves.

Bear in mind; strawberries struggle in acidic soil. High acidity levels can turn the plants yellow in spring, summer, and fall.

2- Direct Sunlight 

Choosing the wrong plot for strawberries often leads to not providing even minimal shading. When bushes endure direct sunlight all day, they likely suffer from dryness, yellowing of leaves, and sunburns.

On the other hand, this issue hits very young bushes and older plants particularly hard.

Arrange the beds to receive sunlight and shade throughout the day. Planting crops like onions nearby can offer slight shading.

3- Lack of Water 

The development of strawberries suffers if the water supply is poor. These berries thrive with plenty of water.

Without the necessary moisture, the plant’s root system poorly absorbs nutrients from the soil. Regular watering is key, but be careful not to overwater.

Too much water can lead to waterlogging, root rot, and the plant might even die. Overwatering also boosts fungus-related diseases.

These problems compromise leaf health leading to wilting, yellowing, and dryness. To water correctly, monitor the soil’s condition closely.

Water it when it’s slightly dry. Aim for about 3 gallons (11 liters) of water per square yard (meter) of the plantation. Mulch around the bushes to keep water in the soil. Use pine needles, straw, or freshly mown grass for this.

4- Microelement Deficiency 

When your strawberry leaves start turning yellow, you can bet your bottom dollar that it’s often due to a lack of nutrients and microelements.

Say, for instance, you’ve been playing fast and loose with crop rotation, or you’ve set up your beds after the wrong crops, then you’re likely to run into a vitamin shortage.

Planting strawberries after eggplants, potatoes, peppers, and tomatoes is like trying to squeeze blood from a stone – they just sap the soil dry and strawberries can’t handle a poor diet.

Here’s my two cents: strawberries are best off following radishes, carrots, onions, garlic, any kind of greens, legumes, and green manure crops.

Magnesium

Magnesium is the usual suspect when it comes to soil deficiencies. It’s the ringleader that can turn your foliage yellow, brown, and even purple.

To nip it in the bud, add fertilizers with magnesium sulfate, either in solution or dry form. Just remember, it’s not a one-shot deal – you’ll need to do this twice, with a week’s breather in between.

Nitrogen

When it comes to nitrogen, springtime is when it tends to go AWOL. The root system has a hard time getting nutrition from cold soil, and you might notice your leaves turning slightly yellow or going full-on lemon.

To turn the tables, bring in ammonium nitrate diluted in water. For every 2.6 gallons (10 liters) of water, throw in 30g of the stuff.

Boron

Boron deficiency isn’t just a one-trick pony. It doesn’t just change leaf color but can also stunt flower growth, leading to irregularly shaped fruit.

Get some feedings with boric acid underway to hit this problem on the head. You’ve got two recipes to pick from.

The first one calls for a small spoonful of boric acid, a cup of ash, and 30 drops of iodine per 2.5 gallons (10 liters) of water.

The other version is half a cup of ash, a large spoonful of urea, half a small spoonful of boric acid, and 0.11 oz (3g) of manganese for the same amount of water. Mix whichever variant you choose well and then use it for spraying.

Iron

The iron shortage doesn’t crop up as often, but it can throw a real monkey wrench in the works when it does. It’s not hard to spot – young leaves start turning yellowish between the veins.

If your garden soil leans more toward alkaline, you have a perfect storm for this problem. Bring in big guns to fight fire with fire: special products like chelated iron liquid. 

But keep an eye on the soil’s acidity level: if it’s only slightly acidic, you’re good on the iron front. But if you’re dealing with acidic soil, you’ll likely be in for a bumpy ride.

5- Battling Potential Diseases

Adjusting fertilization or tweaking your farming practices can’t fix every problem in your garden. Sometimes, illnesses and pest attacks mess with your plant leaves’ appearance.

These issues will need some extra care. Luckily, we can diagnose several ailments based on similar symptoms.

Tackling Gray Mold

Gray mold – it’s a serious issue. It can leap from other crops or flower beds and ambush your strawberries. Here’s what you need to look for when dealing with this disease:

• Notice small, brown spots that grow over time?
• Do your fruits seem to soften, lose their color, and start to rot without falling off?
• Are your leaves starting to dry up and turn yellow?
• Is a gray fluff gradually creeping over your entire plant?

The trick here is that identifying gray mold in its early stages can be challenging. Your plant could look as if it’s just chilling out in the sun when it’s actually under attack.

This is a sneaky fungal disease that usually sets up camp in the soil and targets mature plants. The sad truth is, curing gray mold is pretty much a lost cause.

If things start looking dire, your best bet is to dig up the plant and get rid of it. The quicker you act, the less risk there is to your other crops.

Once the plant is history, don’t forget about the soil. The fungal spores can hang out there for years.

You’ve got a few options for disinfecting the soil – you can use a Bordeaux mixture, a light solution of potassium permanganate (KMnO4), or a copper sulfate (CuSO4) solution.

After you’ve sprayed your soil, hold off on harvesting any fruits for about two weeks. That way, you give your crop the best chance at a fresh start.

Powdery Mildew

Powdery mildew is a common problem, especially for strawberries with weakened immunity. The disease first affects the leaves, then moves onto the stem, and finally, the berries.

If an infection occurs during the fruiting period, it can lead to a loss of taste and deformities.

Here’s what you should look out for:

• Leaves curling;
• They stop growing, change color, and dry out;
• A white coating appears on leaves, stems, and fruits.

In a greenhouse, the risk of infection is higher due to the increased humidity and warmth. It’s essential to ventilate daily, preferably more than once, and monitor humidity.

If you discover an infection, here’s what you can do:

• Water or spray with diluted milk or whey, using one part dairy product to three parts water;
• A solution of ash is completely harmless to the crop. Let it steep for four days in a 1:10 ratio, then water the soil with it;
• Dish soap is very helpful – dissolve one bar in a 2.6 gallons (10 liters) bucket. It’s essential to dissolve it completely;
• Spraying with copper sulfate is an excellent method, especially if you add 0.7 ounces (20 grams) of soap to the solution;
• 5 ml of iodine in 1.3 gallons (5 liters) of water is a safe preventative and effective treatment.

Tackling Verticillium Wilt

Verticillium wilt, a fungal-based disease, is arguably one of the most dangerous threats to your garden.

Spores of this fungus can lurk in the soil for decades, and the slightest contact with a gardener’s tools can trigger an infection.

Here are some symptoms to watch out for:

• Yellowing and drying out of the leaves at the bottom of the plant, which then turn red or brown;
• Withering of the entire plant;
• Eventual drying out of the plant;
• Reddening of stalks and shrinking of the above-ground parts of the plant.

Sadly, you can’t cure this disease without resorting to potent chemical treatments, and even then, the plant might not survive.

The disease typically shows up during fruit formation, so you can bid your harvest goodbye.

The best course of action is to uproot and destroy the infected plant, then treat the soil with specialized agents or a Bordeaux mixture. Remember, these treatments aren’t safe to use during harvest time.

Addressing Leaf Spot Diseases

Strawberries can fall victim to several types of leaf spot diseases, including white and brown spots.

These start as small spots on the leaves, gradually growing larger and eventually forming a hole in the leaf.

Since there’s no effective treatment for leaf spots, you should remove and destroy any infected plants. You can then treat the soil with copper sulfate or a Bordeaux mixture with ash.

Phomopsis Leaf Blight

Phytophthora is another leaf-affecting disease. Initially, you’ll notice spots appearing on the leaves, which will then dry out. In the end, the berries may rot, develop a bitter taste, and harden.

Consider using potent chemical agents to manage this, as homemade solutions rarely work. Bordeaux mixture and copper sulfate prove effective.

Remember to apply these chemicals only before forming fruits; otherwise, you must wait three weeks before harvesting.

Keep in mind; diseases aren’t the only threat to your plants. Insects can also cause significant damage. Stay vigilant, as these pests pose a serious risk.

For the treatment of fungal diseases. Here are the fungicides I recommend:

Name of The Fungicide	Amount	Amount of Water
Bonide 811 Copper 4E Fungicide	1-4 tablespoons (.05-2.0 fl oz)	1 gallon of water
Garden Safe Brand Fungicide3	2 tablespoons (1 fl oz)	1 gallon of water
Southern Ag – Liquid Copper Fungicide	3-4 tablespoons	1 gallon of water

6- Potential Strawberry Pests

Strawberry Mite

Tiny in size, the strawberry mite is tough to spot without a microscope. However, the yellowish, dry foliage they leave behind is easily noticeable.

Strawberry plants attacked by mites grow slowly and develop poorly. The risk of infestation increases in high humidity and warm weather.

You can use insecticide and mite killer to eliminate these pests, but be sure not to apply them after fruits have formed.

If the infestation is severe, mowing down the bushes and treating the soil and plant residues is best.

Weevils

Weevils are black-gray beetles with hairy bodies and curved snouts. You can eliminate them with a baking soda solution—two big spoons in half a gallon (2 liters) of water should do the trick. You can also use a solution of laundry soap and ash for spraying.

Slugs

Slugs are most active during the night, so in the morning, you can handpick them off your plants and dispose of them. Placing slate pieces between plantings makes the slugs more noticeable.

To deter them, mulch the soil with pine needles or sawdust. Spraying strawberries with mustard ash can help eradicate these pests.

Nematodes

These extremely thin, semi-transparent worms suck the sap from strawberries, causing the leaves to yellow and dry up.

Prevention is the best strategy here—dusting the soil between rows with lime helps.

During fruiting season, spray the plants with the copper fungicide mentioned above or a garlic infusion. Alternatively, you could plant garlic nearby.

Preventing Diseases

You can take several actions to prevent pest attacks and strawberry diseases.

• Mulching: Changing the mulch regularly helps keep the leaves from yellowing due to many diseases. Black non-woven material, straw, or dry sawdust are ideal options.
• Spraying: Regular sprays, for example, with a Bordeaux mixture, can help prevent diseases. You should spray three times during the growing period, preferably in the evening. You can also use a solution of copper-based fungicide and lime.
• Feeding: Fertilizing your plants promptly boosts their strength and immunity. For instance, regularly watering them with a wood ash solution can be very beneficial.
• Crop rotation: It’s a good idea to replant your strawberries every five years and avoid planting anything else on the old spot for about the same time.
• Proper watering: While strawberries love moisture, it’s crucial not to overwater them. Avoid water stagnation, as this can increase the risk of fungal diseases.