What’s That Foam on My Plants? Get To Know Spittlebugs

Have you ever noticed a frothy patch of spittle on one of your garden plants? I have! Just the other day, I walked past my rosemary, and right on a leaf was a patch of spittle. It looked like someone had walked by and spat on my plant. But it isn’t spit. It’s a sign of spittlebugs.

Most of the time, spittlebugs aren’t much of a problem. While spittlebugs suck the sap from a variety of plants, they’re tiny, and incapable of much damage.

But occasionally, large groups of spittlebugs congregate. When they do, expect to see noticeable damage on your ornamental plants, herbs, and veggies. They can even spread disease. Here’s what to do:

Recognizing Spittlebugs in Your Garden

There was a time, I might have asked my kids if they’d been spitting on the herbs, but now I know better. After a little exploration and a lot of research, I know that those bubbly spitballs on my plants aren’t human spit at all – they belong to the spittlebug.

The easiest way to find spittlebugs in your garden is to look for the tell-tale sign of those frothy bubbles on your plants. If you’ve ever tried to recreate spittle bug “spittle,” you’ll find that it’s not easy to do at all. Human spittle doesn’t maintain its shape on a leaf the way spittlebug spittle does.

When you see a little spot of spitty-looking bubbles in your yard or garden, look again. It’s most likely a spittle bug secretion.

Spittlebugs are also known as froghoppers. Adult froghoppers jump from plant to plant. Adult froghoppers are usually under a quarter-inch long. They often sport contrasting colors on their bodies. Adult froghoppers can jump far and high.

Despite all this, they’re easy to miss in the garden. Unlike the larvae spittle-masses, adults are well-practiced at sneaking around unseen. You may catch a glimpse or two, but these little pests are hard to find.

The easiest way to recognize spittlebugs in the garden is in the tell-tale patches of spittle. These bundles of bubbles act to protect the nymphs as they feed. Spittlebug larvae are small and soft-bodied, so you’d be tempted to think of them as vulnerable creatures.

But the spittle that distinguishes these pests from other garden insects is also a powerful shield. Spittlebug spittle protects these tiny larvae from predators, pesticides, and threatening weather – like bright sunlight.

Life Cycle of a Spittle Bug

In late summer, adult froghoppers lay their eggs in plant debris like dead leaves, fading flowers, and other garden clutter. They overwinter as eggs and then hatch in the spring to start feeding as spittle bug larvae.

Usually, the larvae start feeding at the base of a nearby plant and slowly work their way upward.

Spittlebug larvae go through five stages of larval life before transforming into adult froghoppers. In each of those stages, the spittlebugs get a little bigger and their color changes slightly from pale green to brownish beige.

After a few weeks of growing through the larval stages, our nearly-grown spittle bugs retreat into their spittle to complete the change from larvae to adult. When the adults emerge, they’re tougher creatures with strong hind legs.

Adult spittlebugs jump from plant to plant, feeding and mating for the last six months or so of life before dying as the weather cools.

What is That White Spittle Stuff?

The foam that is the defining feature of spittlebugs (or froghopper) larvae is actually excreted from the rear of the larvae. Sometimes referred to as the larvae’s urine, the spittle is created as the spittlebug larvae feed and then froth up and excrete the substance \ to provide an easy and close-at-hand hideout for the young pest.

With so much outside protection, spittlebugs don’t need to worry about a lot. These little guys just spend their days wandering, slowly up a plant, eating and leaving a trail of spittle as they go.

Spittlebugs are usually at least partially protected by their frothy homes. When they feel threatened, like when you walk by, they can retreat completely into their wads of spit. They can even stop breathing for brief periods of time – or pop a few of the bubbles to breathe inside the spittle cluster until you go away.

When it’s time to grow into adult froghoppers, your little spittlebugs will hide away inside an extra-large (for them) bubble and transform into an adult. Once that happens, the froghopper has no need for spittle. Your plants will be free from unsightly bubbles until next spring.

Do Spittle Bugs Harm Plants?

Spittlebugs feed off of our beautiful garden plants. They especially love roses, junipers, strongly scented herbs, and pine trees. But you can find them anywhere. I’ve seen spittlebugs on grasses and clover as well as rosemary and birch.

Unless you have a huge infestation, though, spittlebugs are pretty harmless. They rarely even cause minor, visible damage. In a world full of garden pests, spittlebugs are the least of your worries.

Since spittle bugs only stay on the plants for a few weeks in the spring and early summer, they’re a very minor pest. The adults also feed on plants, but tend to hop around, feeding a little here and a little there. Neither the adults nor the larvae present a threat to healthy plants.

They can cause tip dieback, which can be unsightly, but it won’t kill your plant.

While spittlebugs themselves don’t cause a lot of damage, they can spread plant diseases. For that reason, it’s worth keeping them under control. That’s what we’ll discuss next.

Preventing Spittlebugs

Even though spittlebugs aren’t usually harmful, you may want to keep them out of your garden anyway.

Little patches of frothy white bubbles on your plants aren’t exactly attractive. You may not be able to keep these little guys out of your garden completely, but you can make life difficult for them.

1. Clean Up the Garden

To stop spittlebugs from hatching in the first place, clean up your garden in the fall. Rake away dead leaves, sticks, and weeds. Keep some breathing room between your plants to make it difficult for eggs laid in last year’s weed to hatch under your prize rose bush.

Consistent yard care and a bit of “putting the garden to bed” clean-up in the fall can do wonders.

Spittlebug eggs won’t hatch in your garden if they’ve been raked away. These little guys are so slow and localized in the larval stages. They’re only up for very short journeys – from last year’s leaf to the plant right beside it.

2. Water Pressure

If you do find a few patches of spittlebug spittle the best way to get rid of it is with a strong spray of water from the hose. Really, it’s that simple. Remember that these little larvae aren’t big travelers. Once you push them off the plant with a strong spray of water, they’re practically helpless.

Direct a strong spray of water at the patch of spittle and send it into the dirt. Without the protective bubbles, the larvae will probably die quickly. They have a host of predators that will be happy to jump on helpless spittle bug larvae.

Spiders, assassin bugs, and wasps are just waiting to stumble on a spittle-less spittle bug.

3. The Unpleasant Option

Of course, the easiest way to get rid of spittlebug larvae is to simply wipe them up. Grab a rag and wipe up all those patches of bubbly residue, and the tiny larvae within. Ewww, right?

It’s not really as gross as it sounds. I promise, you probably won’t even notice those tiny larvae. The spittle is a little sticky, but it’s not much worse than wiping away spider webs. But, if you have access to a hose with a strong spray nozzle, there’s really no reason to just wipe away the foam.

4. What About Pesticides?

The jury is still out. Some sources say that pesticides can’t penetrate the protective spittle. Many gardeners have found that most pesticides aren’t effective against spittle bug larvae. Pesticides can help limit the number of adult froghoppers hopping around, but it’s not a strong weapon against the well-protected larvae.

Plus, conventional pesticides often harm beneficial insects, too. This can lead to a whole host of other problems in your garden. Since they aren’t a serious problem and they’re fairly easy to control, avoid using pesticides against spittlebugs.

5. A Home-Made Solution

If you’re hoping to drive away both spittlebug larvae and the adults, try making your garden unattractive to them. Spray them with a strong stream of a spicy mixture of water, garlic, onions, and red pepper.

You could also mix in a little liquid soap so that if any of the spray touches the larvae, it’ll have the effect of insecticidal soap.

This recipe calls for one cup of water, one tablespoon of dish soap, four cloves of peeled garlic, and one jalapeno, diced (with seeds). Puree the whole mixture together and leave it to sit overnight for at least eight hours.

Then, strain out the solid matter and put it in a spray bottle. Use this spray after removing the spittle from your plants. Spray the woody parts of the plant after each rainstorm to continue deterring spittlebugs all summer long.