Strawberry plants, a staple in many gardens, can be surprisingly susceptible to common pests and diseases. While they’re considered easy to cultivate, it’s crucial to be aware of these issues to ensure a bountiful harvest. In my first year of growing strawberries, I was caught off guard by an aphid infestation that decimated most of my crop. It was then that I realized the importance of understanding and mitigating strawberry pests and diseases.
With this knowledge, I’ve been able to protect my plants and enjoy a more successful harvest. Here are some of the most prevalent strawberry pests and diseases to watch out for.
14 Common Strawberry Pests
While strawberries are undoubtedly a sweet treat for humans, they also hold a special appeal for many insect species. Unfortunately, this popularity has led to a range of pests that can cause significant damage to strawberry crops. In fact, there are numerous culprits waiting to take a bite out of your berries. Let’s take a look at some of the most common offenders.
Aphids
Aphids are a ubiquitous gardening nemesis, making them a common culprit when it comes to strawberry pests. These tiny, soft-bodied insects have a penchant for congregating on the undersides of leaves and stems, where they feast on sap and leave behind a sticky residue known as honeydew that can attract other unwanted visitors – pests and diseases alike. While minor infestations typically don’t pose significant threats, severe outbreaks can decimate entire crops.
To protect your strawberry patch from these pesky invaders, be sure to consult our comprehensive guide on how to effectively eliminate aphids in your garden.
Armyworm
Armyworms are notorious for their destructive feeding habits, leaving behind a trail of irregularly shaped holes on leaves that can quickly lead to skeletonized foliage and dry wounds. The telltale signs of heavy infestation include egg clusters on the leaves, with each generation producing 3-5 generations per year. In terms of organic control methods, introducing natural predators or applying Bacillus thuringiensis have proven effective in managing these pests.
For a comprehensive guide to tackling armyworms in your garden, take a look at our resource.
Japanese Beetle
Japanese beetles are unmistakable with their vibrant green-copper hue and 13mm length. As adults, they wreak havoc by skeletonizing leaves and causing irreparable damage to flowers. If left unchecked, these pests can devastate plants. A simple yet effective method of defense is deploying floating row covers, which prevent the beetles from reaching your plants in the first place.
For an added layer of protection, you can manually remove any spotted adult beetles and dispose of them in a soapy solution. Additionally, introducing parasitic nematodes to the soil can significantly reduce Japanese beetle populations that survive the winter months. If you’re facing a full-blown infestation, consider resorting to neem oil or insecticidal soap sprays to curb the beetle population’s growth.
Loopers
One of the most pervasive strawberry pests is loopers, characterized by their extensive damage caused by large and/or small holes left behind. These pale green caterpillars have distinctive white or cream lines running down either side of their body, typically targeting the lower leaves of plants. To manage looper populations effectively, consider encouraging and releasing natural enemies in your garden, as well as manually removing them from affected areas.
If these methods prove insufficient, Bacillus thuringiensis can be applied to kill the larvae, ensuring a targeted solution without harming beneficial insects that are vital to your garden’s ecosystem.
Slugs
While most people are familiar with the physical appearance of slugs, many may not be aware of the damage they cause in gardens. These unwanted visitors leave behind irregularly shaped holes in leaves and stems, as well as eat through ripening fruit. In severe cases, infestations can even lead to shredded leaves. To effectively manage these pests, it’s essential to remove any garden debris, weeds, and trash, as this reduces their hiding places.
Additionally, regular night-time hand-picking of slugs from plants is a simple yet effective method for controlling the population. Furthermore, spreading eggshells around affected areas can also help deter them. By implementing these methods, you’ll be well on your way to a slug-free garden.
Strawberry Spider Mites
Strawberry spider mites and other species of spider mites can be particularly infuriating pests for strawberry growers, given their tiny size that makes them challenging to manage. The presence of these unwanted visitors is often accompanied by a telltale sign: yellow stippled leaves and bronzed foliage. A closer inspection may also reveal web-covered leaves and the tiny mites scurrying across the webs or undersides of the leaves.
To combat this issue, one effective approach is to blast the plants with a powerful jet of water, which can help reduce the spider mite population in your garden. Additionally, insecticidal soaps and various insecticides can be used to decrease the population, provided they are specifically labeled as being effective against spider mites.
Thrips
The damage caused by thrips on strawberry plants is characterized by the browning of anthers and stigmas, a consequence of these tiny insects’ presence. To spot them, you’ll need a magnifying glass to get up close, as they’re remarkably small. Adult thrips are typically pale yellow to light brown in color, with their nymph stages being even smaller and lighter.
It’s no surprise then that they tend to appear most prominently during the spring season, when they can be found on weeds and crops like strawberries. To keep them at bay, incorporating reflective mulches into your garden strategy is an effective deterrent. Alternatively, if thrips become a significant issue, using targeted insecticides may also help manage their impact.
Weevils
Weevils can significantly impact the health and appearance of your plants, causing characteristic notches in leaves, stunted growth, and tightly clustered foliage. The adult weevils themselves display a range of brown hues, while their larvae take on a creamy or white color as they feed on plant roots.
To prevent weevil infestations from taking hold in your strawberry patch, it’s essential to maintain a weed-free environment.
When planning your garden layout, be mindful not to place strawberries too close to blackberries and elderberries, which are known hotspots for weevil activity. If you do encounter an outbreak, pyrethroid-based pesticides can provide effective control measures.
Tarnished Plant Bugs
Tarnished plant bugs (Lygus lineolaris) are a common menace to young strawberry plants. If left unchecked, these pests can cause significant damage and ruin your harvest. The good news is that the damage is minimal if you address the issue promptly. Identifying adult tarnished plant bugs is relatively straightforward; they have a distinctive yellow, brown, and black body, as well as a small yellow ‘V’ shape behind their head, making them easily distinguishable from other pests.
Younger specimens, however, can be mistaken for aphids due to their pale green color and smaller size. Despite their short lifespan of just 30-40 days, tarnished plant bugs can wreak havoc during this time by feeding on the sap of the plant and spreading diseases. They use their sucking mouthparts to acquire their preferred food source, which is the sap of the strawberry plant.
These pests thrive in environments with weeds and other cover plants, so it’s essential to keep your strawberries isolated from bushes, shrubs, and trees, and maintain a weed-free zone. To encourage natural predators, consider planting strawberries near pollen-producing plants. If the issue persists, an insecticide containing pyrethrin, such as PyGanic Gardening, can be an effective treatment option.
Sap Beetles
Strawberry sap beetles (Stelidota geminata) are tiny insects characterized by their oval-shaped bodies. Typically, they have dark-colored bodies with yellow or orange spots, and it’s the adult stage that poses the greatest threat to strawberry plants. Unlike other pests, these beetles have a peculiar taste for damaged fruit, making them particularly problematic during harvesting when berries are ripe. The first indication of an infestation is usually the appearance of small holes in the berry.
If left unchecked, these pests can cause massive damage, leaving large holes on one side of the fruit. It’s essential to exercise caution with sap beetles as they can migrate to other plants and wreak havoc, too. To prevent infestations, remove any dead fruit or damaged leaves immediately, avoid damaging the fruit when pruning or working around your strawberry patch, and keep a close eye on your plants after heavy rainfall events, which create an ideal environment for these pests.
As a last resort, consider using insecticides containing pyrethrin to manage these pests.
Spittlebugs
Spittlebugs, also known as froghoppers, can have a significant impact on your berry production by reducing fruit size and hindering growth. These pests are relatively easy to identify, as they leave behind a characteristic foamy residue on the plant when inspected for damage. Belonging to the Cercopoidea family, it’s essential to address these issues promptly when the foam symptoms appear, as this is often an indication that young insects are seeking refuge from predators.
While spittlebugs won’t necessarily cause the death of your plant, they can significantly stunt its growth if left unchecked, potentially resulting in a reduced harvest the following year. If you catch the pests in their early stages, a gentle spraying with water can be an effective method for removal. For more detailed guidance and additional tips, please refer to our comprehensive resource.
Root Weevils
The strawberry plant is susceptible to infestation by three main pests: strawberry root weevils (Otiorhynchus ovatus), rough strawberry weevils (O. rugosostriatus), and black vine weevils (O. sulcatus). These pests target the roots of young plants, but will also feed on older strawberries. The problem with treating these pests is that they typically burrow into the plant’s roots, making it difficult to control them unless caught in their early stages.
Adult root weevils are brown or black, measuring approximately 1/3 inch long, and feed on strawberry leaves. They emerge from the plant in late May or summer, but only forage at night. Some species of root weevils will only eat for 10-14 days, while others will consume for 30-60 days before laying eggs. The real challenge begins once the eggs are laid. The eggs overwinter in the ground and hatch into larvae in the spring, which then feed on strawberry roots.
To combat this issue, turn over the soil in the winter or early spring before planting to expose the eggs and larvae to natural predators such as birds. Once your plants are in the ground, place cardboard barriers next to them. The adults will hide under the cardboard, allowing you to lift it up and inspect for the pests. If found, it’s time to take action. A product containing Bacillus thuringiensis, a beneficial bacteria, can be used to kill eggs, larvae, and adults.
Additionally, beneficial nematodes, which are available on Amazon, have proven highly effective in controlling larvae and eggs.
Spotted Wing Drosophila
The spotted wing drosophila (Drosophila suzukii) is another common pest that infests strawberry plants. Adult females will deposit their eggs on ripening strawberries, allowing the larvae to emerge later as fully formed flies. The larvae’s life cycle is characterized by a brief 30-40 day span during which they can lay hundreds of eggs. It’s often difficult to detect their presence without utilizing a vinegar trap.
As the larvae develop, you may start to notice sunken spots and rot on the strawberries, but it’s only when harvesting that you might discover the wriggling maggots inside. While it’s understandable that some people might find the idea of consuming fly larvae unsettling, rest assured that they pose no harm to human health. In fact, it’s likely you’ve unknowingly ingested them before.
For those who are uneasy with this prospect, simply soaking berries for 10 minutes can encourage the maggots to emerge and render them harmless. Alternatively, using netting to cover plants will prevent adult flies from laying eggs in the first place, effectively eliminating the issue.
Herbivores
Strawberry pests aren’t just about bugs – herbivores can cause significant damage to your crop. While it’s wonderful to have wildlife visit your garden, some creatures can be detrimental to your strawberry plants. Animals like rats, squirrels, moles, rabbits, mice, chipmunks, birds, and deer are all attracted to strawberries. To protect your fruit from these unwanted visitors, consider building a fence that extends two inches into the ground and reaches six feet in height.
This will keep out rodents without harming the animals. Alternatively, you can use chicken wire or wood/metal fencing for added protection. For bird control, netting is an effective solution. It’s also crucial to site your strawberry plants carefully, keeping them away from rodent habitats like woodlands and maintaining short grass to discourage mice and rats from making themselves at home in your garden.
Raised beds are a great way to grow strawberries, providing natural barriers against burrowing animals and separating the fruit from other plants.
5 Common Strawberry Diseases
To safeguard the health of your strawberry plants, it’s crucial to be aware of the common diseases that can wreak havoc on their well-being. Prolonged infections can have devastating consequences, including the demise of your entire crop. To minimize the risk, take proactive steps in your garden by maintaining a clean environment, ensuring adequate spacing between plants, and providing optimal watering and fertilization practices.
By doing so, you’ll be better equipped to prevent the onset of these diseases and ensure a bountiful harvest.
Angular Leaf Spot
Angular leaf spot, a bacterial disease, manifests as small, water-soaked lesions on the lower surfaces of strawberry leaves. As time passes, these lesions enlarge and transition from green to dark green before eventually oozing. This pathogen persists in crop debris, overwintering on the plants themselves. While it can survive for extended periods in this debris, it is unable to withstand soil conditions.
The bacteria’s spread is facilitated by splashing water from overhead irrigation, which dislodges the pathogens and allows them to colonize new areas. Regrettably, eradicating angular leaf spot proves challenging, if not impossible. To mitigate the issue, it is essential to plant disease-free stock and rotate crops. Chemical controls are ineffective against this bacterial disease.
Anthracnose
Anthracnose, a widespread fungal disease, manifests on leaves as round black or light gray lesions, often without causing fatal damage to foliage. On stems, it produces dark brown or black, circular marks. For a comprehensive understanding of this disease’s signs and symptoms, consult our in-depth guide. As one of the most prevalent strawberry diseases, anthracnose can be challenging to manage effectively.
To combat this issue, two key strategies are solarizing the soil, which has proven effective, as well as maintaining regular weeding practices, helping to reduce the disease’s spread and impact.
Gray Mold
Gray mold, a prevalent fungal disease, wreaks havoc on strawberry blossoms by turning them brown and lifeless. Its impact extends to the fruit itself, causing unsightly misshapen patches that eventually rot away. A telltale sign of this disease is the appearance of gray mycelium on the affected tissue, which ultimately leads to a desiccated and mummified state.
While it’s impossible to control the weather directly, you can still take steps to regulate your environment and reduce the likelihood of an outbreak. This includes ensuring proper watering at the soil level and maintaining sufficient space between plants. It’s crucial to remove and dispose of any dead or infected material, including decaying fruits, as they can perpetuate the problem.
Applying fungicides is another viable option, though it’s essential to recognize that their effectiveness is not guaranteed. A combination of these measures may be necessary to effectively manage gray mold.
Leaf Scorch
Leaf scorch, a fungal disease, manifests as irregular dark purple or brown blotches on the upper leaf surfaces, gradually evolving into larger purplish-brown patches. The tissue between these blotches often turns purple or red over time. Furthermore, the disease affects flowers and fruits, causing lesions to form, which can lead to withered petals dropping off the plant and even fruit death. Conditions that facilitate leaf scorch include prolonged foliage wetness.
To mitigate this issue, it’s crucial to maintain good air circulation and soil drainage in your strawberry plants. Additionally, applying foliar fungicide may provide sufficient control measures.
Powdery Mildew
Powdery mildew is a ubiquitous fungal affliction that can wreak havoc on your garden, causing patches of fuzzy white growth to appear on the undersides of leaves. As these lesions expand, you may also notice purple-red blotches developing on the lower leaf surfaces. If left unchecked, powdery mildew can have devastating consequences for your plants, potentially rendering them incapable of producing fruit altogether.
The disease is characterized by its ability to overwinter on leaves and spread rapidly through the air, making it essential to take proactive measures at the first signs of infection. A protective fungicide application can be an effective deterrent against further spread, giving you a fighting chance to reclaim your garden from this insidious invader. For more information on how to prevent and manage powdery mildew in your own backyard, check out our comprehensive guide.
