Organic Flea Beetle Control

Of all the garden pests to be had, the Flea Beetle ranks as one of my favorites. Yes, I used the words favorite and pests in the same sentence! I say this only because the flea beetle turns out to be one of the less destructive and easier to manage garden pests. Well, at least for the container gardener it is. These very small beetles often have a stunning metallic color and are characterized by enlarged hind legs that give them the ability to quickly spring great distances when disturbed. In small numbers, these beetles are actually quite fun to watch jump away when you rustle the foliage of infested plants, but in large numbers, flea beetles can become quite the bane for any gardener. In this guide, learn which edible crops are at risk, identification, and how to implement your own organic flea beetle controls.


Crops at Risk - 

There are many different species of flea beetles, all with somewhat different preferences in plant hosts. Some flea beetles prefer weeds, while some prefer your garden plants! So, which crops are most at risk for flea beetle infestations? Here's a short list:
Though this flea beetle image is not as crisp as the first, it gives you a good
 example of just how small these little pests are. In the background, a
couple of water drops easily dwarf the flea beetle. Furthermore, if you
 enlarge the image, you can sort of see the enlarged rear legs that help the
beetles jump away when startled. 

  • Broccoli
  • Cauliflower
  • Cabbages
  • Horseradish
  • Turnips
  • Mustard
  • Rapeseed
  • Arugula
  • Potatoes
  • Peppers
  • Eggplant
  • Tomatoes
  • Radishes

Flea Beetle Identification - 

Like most other garden pests, the different species of flea beetles will often slightly vary in color and size. With some exceptions, most flea beetles tend to be black or brown in color with a metallic sheen. Others can be striped or reddish. Regardless of color, the tale-tell identifier for all flea beetles is their characteristic enlarged rear legs. These large hind legs allow them to jump from plants when they are disturbed. So, if you notice little bugs springing away from your plants as you rustle the leaves, flea beetles are most likely present!

Another identifying tool is the damage that they leave behind on plant foliage. On tender new growth, flea beetles eat away the surface of leaves, leaving a characteristic "buckshot" type pattern. If your plants look like they've been shot with a very tiny shotgun, it's more than likely that flea beetles are the source of destruction. Damage will often only be viewed on seedlings, young plants and tender new growth. As crops get older (3-4 true sets of leaves), the leaf surface grows a thicker cuticle that becomes much harder for the beetles to feed on. 

Organic Flea Beetle Control - 

Prevention - Flea beetles are pretty crafty in their approach to infestation, so 100% prevention may not always be possible. Fortunately, there are a few ways in which infestations can be mostly avoided!
Radish leaf showing flea beetle damage. Their
eating of the external leaf surface creates
the classic "buckshot" pattern. I had a rather
small infestation, so no measures were taken
to get rid of them. The radishes? Well, they
turned out just fine!

  • Crop Rotation - The simple measure of crop rotation can work as the saving grace for your garden. See, when flea beetles find their preferred crop to feast on, reproduction is not far behind. This often means that the flea beetles will lay eggs at the base and in the soil surrounding the crop. Larvae quickly hatch and do their own number by feeding off roots until winter forces them into dormancy. If the same family of crops is planted back into the area of infestation, you're basically handing larvae, and the subsequent adult beetles, a free meal!
  • Floating Row Covers - If expenses permit, floating row covers are a great option for preventing infestations of many different flying pests, including flea beetles. For the greatest success rates, make sure that they are completely sealed. Remember to use crop rotation in conjunction with row covers, or else you'll just be trapping in a potential infestation. 
  • Trap Crops - Without floating row covers, cruciferous (cabbage, broccoli, turnips, etc.) seedlings and young plants are susceptible to adult beetles. To help reduce damage, a "trap crop" of radishes can be planted so that it completely surrounds the more important crops. The beetles tend to land on the first crop they prefer, so the radishes will effectively act as a barrier, catching beetles before they get to the plants in the middle. The radishes will be just fine, as they grow quick enough to easily brunt the damage of the flea beetles. 
  • Companion Planting - As flea beetles search for food, they take to the air and sense out chemical odors from their preferred hosts. By planting stronger smelling species, the gardener is able to mask the sent of flea beetle prone plants. Catnip, thyme, basil and other members of the mint family interlaced throughout the prone plants will confuse passing by flea beetles. 

Radish leaf with a flea beetle on the outlook. 
Vigilance - Even if you've implemented preventative measures, vigilance from the gardener is an absolute must. On a daily basis, plants should be inspected for pests and diseases anyways, so looking for the flea beetles should be routine. If flea beetles are identified, try not to rustle foliage until you can get an accurate number of beetles present. Should there only be a few flea beetles, you may just want to scare them off by brushing them from the leaves. Large populations of flea beetles may require treatment.

Natural Flea Beetle Control - Insecticidal soap sprays are often ineffective on flea beetles, but garlic and hot chili powder seems to do the trick! If large populations are present, completely crush a couple cloves of garlic and add to one quart of water. To the garlic water, add two teaspoons of finely ground chili powder and one teaspoon molasses (for adhering to the leaf surface). Let the mix sit in the fridge overnight, strain, and then spray onto the foliage during the early morning hours. Between the strong odor of garlic and the heat of the chili powder, flea beetles will be deterred from eating further. 

With that, we've reached a conclusion for organic flea beetle control. With preventative measures and good gardening practices, flea beetles can easily be deterred from your garden. More importantly, not a drop of toxic insecticide was used in the process! Thanks for reading this guide on controlling flea beetles organically.