Shiny little jumping pests that love to munch on garden crops, flea beetles feed on the leaves, roots, and tubers of plants in the Brassicaceae and Solanaceae families.
They choose their host plants by smell as well as by sight. A flea beetle infestation can cause significant damage to your vegetable garden. Therefore, exploring ways to get rid of them should be your main priority.
Flea beetles are of the family Chrysomelidae. They go through four stages in their lives: egg, larvae, pupae, and adult . They are equally damaging in both larvae and adult stages.
Adults range in size from 1/16 to 1/4 of an inch, and in color from dark brown to bronze to black with several species metallic green, striped-looking, or even blue.
They lay eggs in early spring around the roots of the host plant. The eggs hatch 10 days later, and the larvae go underground to eat and grow.
After hatching in 21 to 35 days, the beetle larvae make cocoons and pupate for about 7-10 days before turning into mature beetles. The adults can both jump and fly.
How to Get Rid of Flea Beetles Naturally
Here are some home remedies and organic solutions that work for these little black bugs.
1. Neem Oil
A botanical insecticide, neem oil is one of the best remedies to get rid of flea beetles organically.
Neem oil repels and deters most insects by disrupting the feeding abilities of the adults and the eating ability and growth of the larvae.
It also masks the scent of your crop, repelling the adult bugs. The treatment helps to prevent plant diseases as well.
Make an organic flea beetle spray by combining 4 teaspoons of neem oil with one teaspoon of organic liquid soap and a gallon of warm water. Shake well and spray on plants.
2. Insecticidal Soap
Made from water, vegetable oil (olive oil or canola), and pure organic liquid soap, this potent soapy water solution kills flea beetles and takes care of most pest problems.
For the recipe, combine 5 tablespoons of liquid soap, one cup of oil, and a gallon of water. Shake well and spray directly onto the beetles.
Moreover, this homemade insecticidal spray will give your plant a nasty taste that will cause other pests to go elsewhere. It will eventually kill them if they meddle too much in it.
3. Companion Planting
Using other plants to help disguise or plant along your prized crops will disrupt their reasoning ability.
Among the many plants that repel flea beetles, you can use dill, catnip, mint, basil, and marigolds to mask both scent and sight of the target plants.
4. Till Soil
Keeping the soil tilled at wintertime will keep the adults dormant for the season. They won’t have the freedom to overwinter in the soil.
Consequently, they will freeze when exposed to the cold. Doing this right after harvest but before fall will kill any larvae.
5. Trap Crops
These are sacrificial plants planted in rows between your crops or on the edges of your garden.
The critters love sunflowers, radishes, and nasturtium. Therefore, planting these will attract them, drawing them away from your vegetables.
6. Sticky Traps
These are mainly utilized to help with identifying an infestation rather than to prevent one. Sticky traps are considered environmentally friendly. Moreover, they are available online and at most farm stores.
Alternatively, make a flea beetle sticky trap using strips of white or yellow plastic coated in something sticky like non-drying glue.
Surround your garden with it. Keep in mind, however, that these traps can also catch other useful insects and bugs including bees and butterflies.
Clover, as well as other living mulch, can help disguise your main crops, making it harder for them to identify the real thing.
Additionally, non-living mulch such as barley straw interferes with the egg-laying process. However, it is vital that you remove mulches at the end of the growing season to keep the adults from overwintering in them.
8. Beauveria bassiana
Beauveria bassiana is an organic flea beetle control remedy .
It doesn’t need to be consumed by them either. Just being touched by the spores will sick the beetles so badly, they will die eventually.
After they die, the fungus will cover their bodies in a layer of mold creating more spores — a perfect pest deterrent.
If you get it from a store to put on your garden yourself, be sure to wear protective clothing and follow the instructions carefully.
9. Coffee Grounds
Using coffee grounds for these black beetles in the garden is a popular remedy among gardeners. It will repel the critters as they hate the smell.
However, be careful which plants you put them around. While they’re a great natural fertilizer, un-composted coffee grounds can adversely affect some plants.
10. Diatomaceous Earth
Used as an organic gardening pesticide, this white powder is fatal to most pests. It cuts up soft-bodied insects like flea beetle larvae, killing them.
Spread it liberally around the base of plants. However, reapply after heavy watering or after there’s rainfall. You can also use it to treat flea beetles in the house.
11. Row Covers
Install row covers over the rows in early spring and before it gets warm enough for the adults to emerge. However, make sure you remove them when the plants start to flower, or your pollinators will have less to feed on.
12. Predators and Parasitic Wasps
Tachinid flies and toads are natural enemies of flea beetles. Braconid wasps also parasitize the pests.
With some research, you can find out which predatory bugs and parasitic wasps are native to your area, as well as how to attract them.
13. Beneficial Nematodes
These fantastic microscopic little roundworms go after the larval stage.
Beneficial nematodes enter their bodies and feed on them. They will remain in the host pest until it dies, then search out another victim.
14. Control Weeds
Pulling out weeds and clearing them out when crop season is over will help prevent adult beetles from overwintering in the garden.
15. Kaolin Clay
This versatile white clay will help mask the scent of the plants that these black beetles love.
Kaolin clay can be mixed with water to form a spray or it can be sprinkled on the plants to keep away the pests.
Flea Beetle Larvae Identification
These tiny fat worms are voracious eaters and just as destructive as the adults. They hatch from eggs having a white appearance with brown heads and tiny legs.
They range in size from ⅛ to ⅓ of an inch in size. The larvae hide under host plants as soon as it is hatched, and it will eat until it’s time for them to pupate.
If they devour the host plant, they will move on to another plant, and they find it more by scent than by sight.
Flea beetles are a type of leaf beetle. They are extremely dangerous in both larvae and adult stages, attacking both ends of the host plant. Adults feed on leaves while the larvae go after tubers and roots.
Adults create irregular holes made in a shotgun pattern or a lacy pattern on the leaves. If they are bothered while eating, they will jump away and return later to continue.
Larvae feed on tubers and roots. They are so minute that it’s hard to remove them once they’re dug in.
On top of the physical damage imposed, they also help spread wilt and blight bacterial diseases while denuding your crops.
As mentioned earlier, the two plant families on which they mainly feed include:
- The Brassicaceae aka Cruciferae, mustards, and cabbage, contain broad-leafed plants. These include cabbage, arugula, spinach, bok choy, broccoli, kale, and root vegetables such as turnips, eggplant, radishes, and horseradish.
- The Solanaceae aka nightshade family contains flowering plants with tubers such as potatoes, and tasty crops like tomatillos, peppers, and Cape gooseberry.
- The tomato flea beetle goes after its namesake.
They also eat lettuce.
This small shiny black beetle is among the worst insect pests a gardener can face. The best way to get rid of them is to avoid getting them in the first place.
However, if you do get an infestation, try the above natural remedies. They are environmentally friendly, and your plants will thank you.