Why Cicadas Won’t Eat Your Tomato Plants

If you live in an area where cicadas are expected to emerge this spring, you might be worried about your garden. You might be wondering whether or not they will impact your tomatoes in particular. Fortunately, cicadas won’t make a meal out of your tomatoes. Although cicadas do feed from vegetation, they do not cause serious damage to the plants they use for food. Keep reading to find out why your tomatoes are safe and whether there are some plants you do need to worry about.

Cicadas Are Not Like Locusts

One of the most common misconceptions about cicadas is that they will strip an area of vegetation after they emerge. This myth comes from the fact that many people assume that cicadas and locusts are the same thing. However, locusts are members of the Acrididae family, along with grasshoppers. Cicadas are members of the Cicadoidea family, and they are closer to aphids and planthoppers.

Locusts look like normal grasshoppers. However, they form gigantic swarms that can be hundreds of square miles. Although they only live a few weeks to a few months, locusts are called a “plague” with good reason. Locusts do not discriminate in what kind of vegetation they consume. Swarms sometimes travel thousands of miles to devour crops, which can result in catastrophic agricultural damage, famine, and starvation.

In contrast, cicadas do not form swarms like locusts, but some species, such as periodical cicadas, can emerge in large numbers. They travel short distances to find mates and lay eggs. Cicadas only eat fluids from trees and woody shrubs and are not known to damage the plants they feed from. They can damage young trees and shrubs by laying their eggs in slits in the twigs, but mature trees typically do not sustain long-term damage. Cicadas do not pose nearly the same threat to an ecosystem as locusts. So there is little cause for alarm when the newest brood arrives in your neighborhood.

What Cicadas Actually Eat

Cicadas feed off xylem, which is the liquid from trees and other woody vegetation. Cicada nymphs typically feed on xylem from plant roots, while adults feed on xylem from trees and shrubs. Cicadas have a mouth similar to the rostrum of a mosquito. This rostrum pierces the tree stem or root and allows the cicada to suck out the liquid. The special saliva that cicadas produce plugs the holes after the rostrum is removed. This ensures that liquid will not leak out of the root or stem.

Unless your trees are small and unhealthy, there is little chance that they will be damaged by cicadas feeding on them. Cicada nymphs are also unlikely to directly damage plants. However, large numbers of hungry cicada nymphs may reduce plant growth.

Cicadas and Your Tomato Plants

As a gardener, you’ll be relieved to know that cicadas won’t be coming to feast on your tomato plants. Cicadas’ mouths were designed to feed on the xylem found in woody trees and plants, not the xylem found in the softer tissues of vegetables and fruits. Cicadas cannot chew solids such as leaves and flesh. Cicada nymphs are also not interested in vegetable plants or stems because they live underground and prefer plant roots.

Although cicadas won’t eat tomato plants, they have been known to feed on fruit trees that produce xylem, such as cherry, apple, and plum. They may also feed on blueberry bushes and grapevines. Cicadas are unlikely to damage mature trees and plants, but young trees and plants can be at risk. So cover them with fine netting to keep the cicadas away.

How Cicadas Might Damage Your Plants or Orchard

Cicadas do little damage via feeding, but they do have a destructive tendency that many gardeners complain about. When a female cicada deposits her eggs, she does so by cutting a v-shaped slit in a tree branch or plant stem and laying the eggs inside. The females lay their eggs near the ends of the branches, causing that section to wither and die. This is known as flagging.

Flagging is rarely an issue for mature, healthy trees. However, cicadas prefer branches between 1/8 inch to around 1/2 inch in diameter. So young trees and shrubs that have mostly small branches are particularly at risk. To protect your young trees and shrubs, cover them with netting so the female cicadas cannot lay their eggs there.

Residents in the areas where cicadas are expected to emerge can rest comfortably in the knowledge that their precious gardens won’t be harmed. Start the season by making sure that your current plants are healthy and not at risk from other parasites. Then, sit back and prepare to enjoy the beautiful cicada hum that will soon be filling the air.