Tomatoes are one of the most popular vegetables grown in home gardens. However, these tasty treats are susceptible to damage from flea beetles. Flea beetle damage on tomato plants can quickly get out of control, leaving you with stunted plants and ruined fruits.
In this comprehensive guide, we will cover everything you need to know about flea beetles and how to prevent and control their damage on tomato plants.
What are Flea Beetles?
Flea beetles are tiny jumping insects that feed on a wide variety of vegetable plants, especially members of the nightshade family like tomatoes, eggplants, and peppers. There are many different species of flea beetles, but some of the most common ones that affect tomatoes are the potato flea beetle, eggplant flea beetle, and tobacco flea beetle.
Adult flea beetles are only about 1/16 to 1/8 inches long They get their name from their enlarged hind legs that allow them to jump quickly like a flea when disturbed Their small size and jumping abilities make them difficult to spot in the garden,
Flea Beetle Life Cycle
The life cycle of flea beetles takes about 4-6 weeks to complete depending on the species and climate conditions.
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Overwintering – Adult flea beetles overwinter in protected areas like leaf litter or under the bark of trees.
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Spring Emergence – Adults become active in spring once temperatures warm up, usually around late April or May
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Feeding & Egg Laying – Adults feed on young seedlings and lay tiny white eggs in soil cracks near the base of host plants.
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Larval Stage – Eggs hatch into slender, worm-like larvae in about 1 week. Larvae feed on roots for 2-3 weeks before pupating in the soil.
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Pupal Stage – The pupal stage lasts 1-2 weeks.
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New Adults Emerge – New adult flea beetles emerge from pupae in the soil to start the cycle again. There are typically 1-2 generations per year.
Recognizing Flea Beetle Damage on Tomato Plants
Flea beetles damage tomato plants in two ways:
Leaf Damage
Adult flea beetles chew many small holes in leaves, giving them a characteristic “shothole” appearance. The holes can range from tiny pinpricks to larger holes nearly 1⁄8 inch wide. Severe feeding can skeletonize entire leaves.
Leaf damage is most serious on young seedlings. A seedling can be killed when 50% or more of its leaf surface area is removed by flea beetles. Mature plants can generally tolerate more foliage loss.
Fruit Damage
Occasionally flea beetles will feed directly on ripe tomato fruits. This damage is usually minor and appears as small holes or pits in the skin, typically just under the calyx.
Fruit feeding is more common late in the season when beetle populations are high and foliage is declining, forcing them to seek other food sources.
Conditions Favoring Flea Beetles
Certain conditions can lead to more severe flea beetle problems:
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Early Plantings – Young spring seedlings are most vulnerable.
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Previous Crops – Damage is often worse in areas previously planted with tomatoes or other flea beetle host crops.
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Field Margins – Infestations tend to start along field edges and borders.
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Hot & Dry Weather – Feeding increases during hot, dry conditions.
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Weedy Fields – Nearby weeds can harbor overwintering flea beetles.
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Reduced Foliage – Late season fruit feeding coincides with fading foliage.
How to Control Flea Beetles on Tomato Plants
Here are some effective strategies for controlling flea beetle damage in the tomato patch:
Remove Nearby Weeds & Crop Debris
Eliminate potential overwintering sites by clearing weeds and leftover plant debris in and around the garden. Tilling in the fall can disrupt any flea beetles sheltering in the soil.
Use Floating Row Covers
Protect young seedlings with lightweight floating row covers. Use them from transplanting or seeding until plants are established. Seal the edges with soil or clips to prevent beetles from getting underneath.
Apply Beneficial Nematodes
Apply insect-killing nematodes like Steinernema or Heterorhabditis species to the soil around plants. The nematodes prey on flea beetle larvae in the soil.
Install Yellow Sticky Traps
The bright yellow color of sticky traps attracts adult flea beetles. Position traps near plants around 6 inches above the ground. Check and replace traps regularly.
Use Repellent Plants Like Catnip or Basil
Interplanting with strongly scented herbs like catnip, sage, hyssop, basil, or mint can help deter flea beetles.
Apply Protective Covers Like Kaolin Clay
Applying a thin kaolin clay spray to leaves can discourage flea beetles from feeding. It forms a mineral barrier that damages their feet and mouthparts.
Use Diatomaceous Earth (DE)
Sprinkle diatomaceous earth, a powdery natural pesticide, on the ground around plants. The sharp DE particles damage the waxy protective coating on flea beetles.
Spray Neem Oil, Pyrethrin, or Insecticidal Soap
Applying neem oil, pyrethrins, or insecticidal soap directly to plants can kill flea beetles on contact. Target the undersides of leaves for best results.
Apply Systemic Insecticides
As a last resort, systemic insecticides like imidacloprid or thiamethoxam applied to the soil or as a foliar spray can provide extended control of flea beetles. Use sparingly to minimize risks to bees and other beneficial insects.
Preventing Future Outbreaks
Once flea beetle damage occurs, it can be difficult to gain control that same season. The best offense is prevention:
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Avoid planting tomatoes in the same location as last year’s plants. Crop rotation disrupts pest cycles.
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Wait until later in spring to transplant seedlings. This allows the first wave of overwintering flea beetles to die off.
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Keep the garden and surrounding areas weed-free to eliminate alternate flea beetle food sources and habitat.
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Use floating row covers at the start of each growing season before flea beetles become active.
Staying vigilant and implementing multiple control strategies at the first sign of flea beetle leaf damage will help protect your tomato crop from extensive losses. Consistent prevention measures over time will minimize recurring problems with these destructive tomato pests.
Damage caused by flea beetles
All types of flea beetles cause similar damage.
- Adult flea beetles cause the most damage by feeding on the leaves and stems.
- They create shallow pits and small rounded, irregular holes (usually less than 1/8 inch) in the leaves. This type of damage is unique to flea beetles.
- Plants started from seeds are less tolerant of feeding damage compared to transplants, but both can be severely injured if flea beetle numbers are high.
- The larvae usually cause little to no damage to the plants (with the exception of potato flea beetle larvae).
A green turnip leaf with irregular holes from flea beetles Flea beetles on collard greens
How to identify flea beetles A black potato flea beetle making holes in a potato leaf
Most adult flea beetles are very small (1/16 –1/8 inch long). An exception is the spinach flea beetle, which is 1/4-inch long.
- Flea beetles can be black, bronze, bluish or brown to metallic gray.
- Some species have stripes.
- All flea beetles have large back legs which they use for jumping, especially when disturbed.
A shiny black crucifer flea beetle making holes in a green leaf
The most common flea beetles in Minnesota:
- Crucifer flea beetle (Phyllotreta cruciferae)
- Striped flea beetle (P. striolata)
- Western black flea beetle (P. pusilla)
- Potato flea beetle (Epitrix cucumeris)
- Spinach flea beetle (Disonycha xanthomelas)
Most flea beetles feed on very specific plants, but the pale-striped flea beetle (Systena blanda) feeds on a variety of plants, like squash, beans, corn, sunflowers, lettuce, potatoes and many weeds.
Pests and Diseases: Flea Beetles on Tomato Plants (See Description)
FAQ
How to treat flea beetles on tomatoes?
If you have moderate flea beetle feeding damage to your Solanaceae plants and you see any early blight starting you’ll need to control both the beetle and the disease. Pyrethroids should work well in controlling flea beetles.
What is the natural enemy of flea beetles?
Natural enemies of flea beetles include Microctonus vittatae (parasitic wasp), entomopathogenic nematodes, white muscadine (fungal pathogen), and generalist predators such as lacewing larvae, adult bigeyed bugs, and damsel bugs. M. vittatae wasps kill flea beetle adults when they emerge after development.
What is the best homemade flea beetle spray?
TL/DR – plant smelly herbs/flowers to deter them. Try this homemade spray to control flea beetles: 2 cups isopropyl alcohol, 5 cups water, and 1 tablespoon liquid soap. Test out the mixture on a leaf of the plant, let it sit overnight, then spray the rest of the plant if you don’t notice any adverse effects.
What is the best flea beetle control?
For severe infestations spray your plants with an “organic” insecticide- pyrethrum, neem, or spinosad. You can also dust plants with diatomaceous earth. Lightly tilling garden soil in spring or fall may also help reduce flea beetle populations.
Are flea beetles harmful to tomato plants?
Flea beetles are common pests of seedling tomatoes in most areas. Adult beetles chew small holes in leaves, giving them a sievelike appearance. The small, slender, white larvae feed on underground parts of the plant, but this damage is not economically significant.
Do flea beetles eat tomato leaves?
Adult flea beetles chew small, round holes in tomato leaves. The holes are about 1/8 inch in diameter or smaller. If flea beetle damage is severe, the leaves take on a lacey, sievelike appearance as more and more of the leaf surface is removed. Seedling tomato plants are the most susceptible to flea beetle damage.
How do you get rid of flea beetles on tomato plants?
Preventive steps for controlling flea beetle damage on tomato plants include growing strong-smelling plants that repel them, such as catnip (Nepeta cataria). However, they can also attack leaves, stems, and fruits of tomato plants, creating tiny holes and preventing proper growth.
Do tomato plants get fleas?
Seedling tomato plants are the most susceptible to flea beetle damage. Mature plants can typically tolerate some feeding. But early damage to young plants can stunt growth and reduce yields. Monitor tomato transplants and seedlings carefully in spring. Check the underside of leaves for the presence of small, jumping beetles.
How do you get rid of fleas on Tomatoes?
Dusting leaves with plain talcum powder repels flea beetles on tomatoes, potatoes, peppers, and other plants. Use white sticky traps to capture flea beetles as they jump. Insecticides may be used early in the season but are generally unnecessary in the control of flea beetles on adult plants.
Do flea beetles damage plants?
New leaves are usually damaged first and will have a lacy appearance. Flea beetles usually don’t cause fatal damage to established plants because the leaves are already large enough to survive a few holes. The real danger is that the beetles can spread bacterial diseases, such as wilt and blight, from plant to plant.