Why Does Your Lawn Look Like It’s Spitting? What to Do if You See Bubbles in the Backyard

If you’ve ever stepped out onto your lawn, only to find what looks like dollops of foamy soap or spit clinging to your grass blades, chances are you’ve seen the spittlebug at work. While it might be a bit of a shock to see your pristine turf looking like it’s been through a car wash, this occurrence is a natural phenomenon. These backyard bubbles are amongst the first of nature's signs that spring has arrived. Spittlebug foam usually pops up around March or April, as the soil starts warming up.

Of course, if you want to stay on top of your lawn care, your first instinct may well be to worry. While it may look like your grass is literally throwing up, don’t worry: it doesn’t mean your lawn is sick! Rest assured, while spittlebugs aren’t exactly beneficial insects in the way ladybugs are, they are far from being garden villains. They are a fascinating marvel in our backyard biodiversity, and they represent a unique survival strategy, so it’s smart to get a handle on spittle season.

Understanding the secrets of the spittlebugs (or froghoppers, as they are also known) is a great way to connect with your outdoor space, especially if you want to protect your turf for a healthier backyard. So if your lawn is in a lather, don’t panic. Whether you wish to take steps to gently prevent or manage spittlebugs, or simply enjoy this natural oddity that shows up each spring, here’s what you need to know.

What is the Spittlebug?

Spittlebugs belong to a diverse group of insects with more than 30 species in North America alone. The insects making the foam are technically the nymphs of the froghopper, in the Cercopidae family. They are close cousins to aphids and cicadas, but they get the froghopper name from the adult's jumping ability. While there are many varieties, the meadow spittlebug (Philaenus spumarius) is the most frequent guest in the backyard, though you might also spot the diamondback or dogwood varieties, depending on your local flora.

They begin as eggs that overwinter tucked into plant stems or leaf litter, waiting for the right temperature to hatch in spring. Once they emerge as nymphs, they are soft-bodied and vulnerable, so they soon set to work building their foamy fortresses. You should take it as a compliment if you see this lawn spittle, as these bugs love areas with high humidity and lush, succulent growth. So if you’ve been diligent about watering and fertilizing your lawns, they are more likely to set up their bubble pads. They dislike dry, windy exposed areas, where their delicate bodies might desiccate.

As they grow, they molt several times over a few months. By summer, they undergo their final transformation, emerging as winged adults. Adult spittlebugs are mottled brown or gray, allowing them to blend into the thatch of your lawn or the bark of your trees, disappearing until the next spring cycle begins. Spittlebug nymphs (usually light green or yellow) are very small and don’t tend to congregate in large numbers, so you’re unlikely to see them without the spittle. If you have a magnifying glass or loupe handy, like the Jarlink Foldable Loupe Magnifier from Amazon, you may be able to get a better look at the nymph nestling in the bubbles.

What’s With The Lawn Spittle?

So where exactly does this white foam on plants come from? To understand the spit behind the spittlebug, it helps to consider a plant's plumbing. Plants have two main vascular tissues: the phloem, which carries sugars from the leaves, and the xylem, which pulls water and minerals up from the roots. Most sap-sucking insects go for the sugary phloem. However, spittlebugs prefer the xylem.

Because xylem sap is mostly water and low in nutrients, the nymph drinks a lot of it. And all that excess fluid has to go somewhere! The nymph excretes the surplus liquid, but doesn't just let it run off. It whips it with air to create a foam, and uses its tail to pull the bubbles over itself until it is submerged. This is a clever survival trick. It keeps the nymph moist in the sun, insulates it against temperature swings, and hides it from predators like birds and spiders that find the bitter bubbles unappetizing.

You’ll notice the foam is most prevalent in the morning or on humid days, when the spit is less likely to evaporate. But while it looks like it’s coming from the grass, it is entirely the work of the bug using the plant's own juice as its raw material.

Are Spittlebugs Harmful to Plants?

Spittlebugs are more of a cosmetic nuisance than a threat. Because they don't usually congregate in massive swarms, the amount of sap they steal from a plant is negligible. You might notice a slight yellowing or a minor curl in a leaf where a nymph has been feeding, but once the bug moves on, a healthy plant will usually bounce back without any intervention.

One exception to this rule is the two lined spittlebug (Prosapia bicincta). This species has a particular fondness for warm-season grasses common in the southern US, such as St. Augustine, Bermuda, and Zoysia. Unlike the meadow variety, a heavy presence of two-lined spittlebugs can cause stippling (small white spots) or even discolored patches of turf.

You might also see a little damage in your strawberry patch if you have an unusually large number of spittlebugs in your garden. Strawberries are a favorite because of their low-to-the-ground, moisture-trapping foliage. If a plant is hosting several nymphs, you might see stunted growth, slightly wilted leaves or lower fruit yield. However, again, the risks of severe damage are minimal with common spittlebugs.

How Do I Manage Spittlebugs?

In most yards, there is no real need to manage spittlebugs as such. In a balanced garden ecosystem, natural predators will eventually find them, or they will simply grow up and fly away. You can simply enjoy the frothy spittle as a welcome sign of spring and let these native insects do their thing. However, if the sight of foam on your lawn is cramping your curb appeal, spittlebug control is quite simple.

A strong blast of water from a hose is usually enough to dislodge the nymphs and break up the foam. Once exposed, these soft-bodied insects are unlikely to make it back onto the plant before they dry out or are snatched up by a passing ant or spider. It’s a chemical-free, instant fix. If you have a recurring problem every year, take a look at your lawn's thatch layer. Spittlebugs love a thick, spongy thatch because it holds moisture and provides a perfect hiding spot for eggs. Dethatching your lawn in the fall can significantly reduce the following spring’s foam party.

Insecticides are not recommended, because the foam acts as a waterproof shield, causing the spray to slide right off. If you are worried about a two lined spittlebug infestation, first spray the foam away with water and then apply an organic option like neem oil. You can buy Bonide Captain Jack’s Neem Oil Spray from Amazon. But a few bubbles here and there is not a problem in most yards. You can probably leave these fascinating little creatures to live out their lives in your beds and lawn.

Give Your Lawn Some Spring TLC

Allowing for spittlebugs, there are a few things you can do now your lawn is waking up to ensure it’s strong enough to handle bubbly visitors. Spring is the time for a proactive spot check. Start by aerating, which involves poking small holes in the garden soil to allow air, water, and nutrients to reach the roots. If your soil is compacted from winter snow or foot traffic, your grass will struggle to compete with weeds and pests, so use a lawn spray or a rotary aerator to free things up.

Once you've aerated, it’s the perfect window for overseeding and topdressing. Fill in those thinning patches with fresh seed, and a light dusting of high-quality compost or topsoil to help create a dense, lush carpet. Finally, add a balanced fertilizer. Use a slow-release formula like The Andersons Professional PGF Complete from Walmart. This will help set your lawn up nicely for even more garden visitors.

Spring Lawn Care Essentials

Effective lawn care starts here, so take steps now to get your sward in order. These lawn-care essentials are the ideal way to tidy up your yard space and optimize one of your biggest attractions for the year ahead.

Frequently Asked Questions

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