Baby stink bugs are called nymphs, and they can look surprisingly different from the shield-shaped adults people recognize. Depending on the species and growth stage, young stink bugs may be black, red, orange, green, brown, or a combination of several colors. They hatch from clusters of eggs laid mainly on plant leaves and pass through several nymph stages before becoming adults. This guide explains what baby stink bugs look like, what they eat, whether they bite or fly, why you may find them around your house or garden, and how to control them.
What Do Baby Stink Bugs Look Like?
Baby stink bugs are miniature, wingless versions of adults, but their body shape and coloration change as they mature. Young stink bugs are generally rounder or more oval than adults. Brown marmorated stink bugs, for example, pass through five nymphal stages and change noticeably in size and color along the way.
Baby Stink Bug Identification
Look for these characteristics:
- Small, round-to-oval body
- Six legs
- Two relatively long antennae
- No fully developed wings
- Red, black, orange, green, or brown coloration
- Small developing wing pads in older nymphs
- Clustered behavior soon after hatching
- Gradually more shield-like shape as they mature
The exact appearance depends heavily on species.
For example, newly hatched brown marmorated stink bug nymphs can appear reddish, yellowish-red, and black. Older nymphs develop pale markings and increasingly resemble adults.
What Color Are Baby Stink Bugs?
There is no single color shared by every baby stink bug. Color can differ between species and even between developmental stages of the same species. This variation is why people sometimes mistake stink bug nymphs for beetles, ladybugs, ticks, or other small insects.
Black and Red Baby Stink Bugs
Brown marmorated stink bug nymphs are particularly striking when young.
Early nymphs may show:
- Black heads
- Black legs
- Red or orange abdominal areas
- Dark markings
- Red eyes
As they continue molting, their coloration becomes more mottled and adult-like.
Green Baby Stink Bugs
Yes, some baby stink bugs can be green.
Green stink bug species may develop green coloration as they mature, helping them blend into leaves and stems.
Because several unrelated insects are also small and green, body shape, antennae, and feeding behavior should be considered before identifying one as a stink bug.
Baby Stink Bug Life Cycle
Stink bugs undergo incomplete metamorphosis, which means there is no caterpillar-like larval or pupal stage. Instead, young stink bugs resemble modified versions of the adults and become progressively more adult-like with every molt.
Brown marmorated stink bugs have five nymphal instars before adulthood.
From Egg to Adult
The basic stink bug life cycle is:
- Egg
- First-instar nymph
- Second-instar nymph
- Third-instar nymph
- Fourth-instar nymph
- Fifth-instar nymph
- Adult stink bug
Females commonly deposit groups of eggs on the undersides of plant leaves.
Brown marmorated stink bug egg masses typically contain about 20–30 eggs. After hatching, first-stage nymphs often remain grouped near the empty eggs before dispersing.
What Do Baby Stink Bugs Eat?
Most commonly encountered plant-feeding stink bug nymphs feed by inserting specialized piercing-sucking mouthparts into plant tissue. Their food preferences vary depending on species and what host plants are available.
Foods Baby Stink Bugs May Feed On
Plant-feeding nymphs may attack:
- Tomatoes
- Peppers
- Beans
- Corn
- Apples
- Peaches
- Pears
- Berries
- Soybeans
- Seeds
- Leaves and stems
- Ornamental plants
Brown marmorated stink bugs have an especially broad host range, including numerous fruit, vegetable, crop, and ornamental plants.
Interestingly, first-instar stink bugs of some species remain around the egg mass and do not begin feeding on plants immediately. Feeding begins after they molt into the next stage.
Baby Stink Bugs on Tomatoes
Tomatoes can attract several plant-feeding stink bug species.
Both older nymphs and adults can insert their mouthparts into developing tomato fruits and suck plant juices.
Signs of Stink Bug Feeding
Affected fruits may develop:
- Pale or yellow spots
- Discolored areas
- Hardened tissue beneath the skin
- Irregular fruit development
- Small feeding punctures
Stink bug damage is usually more important when many nymphs and adults are feeding on the same plants.
Checking the undersides of leaves for egg masses can help gardeners detect them before populations become large.
Baby Stink Bugs in the House
Finding what appears to be baby stink bugs indoors is less typical than finding adults.
Brown marmorated stink bugs commonly enter homes during fall, but they normally overwinter as adults. Their eggs and developing nymphs are generally associated with outdoor plants rather than indoor walls or furniture.
Why You Might See Small Stink Bugs Indoors
Possible explanations include:
- A nymph accidentally entered through an open window
- Nymphs came indoors on a potted plant
- Insects arrived with cut flowers or produce
- Another small insect is being mistaken for a baby stink bug
If dozens of tiny insects suddenly appear indoors, carefully identifying them is important before assuming stink bugs are breeding inside the house.
Do Baby Stink Bugs Fly?
No. Baby stink bugs cannot truly fly.
Nymphs do not yet have fully developed functional wings. As they pass through successive molts, wing pads become increasingly noticeable.
Only after the final molt does the stink bug become a winged adult capable of normal flight.
Do Baby Stink Bugs Jump?
Stink bug nymphs generally move by crawling rather than jumping.
They can move surprisingly quickly across leaves and stems when disturbed, which may give the impression that they are jumping.
An insect repeatedly making strong jumps may be another type of bug.
Do Baby Stink Bugs Bite Humans?
Plant-feeding stink bug nymphs are not normally interested in biting people.
Their piercing mouthparts are primarily adapted for feeding on plant tissues.
They do not seek humans for blood like:
- Mosquitoes
- Bed bugs
- Fleas
- Ticks
However, stink bugs should still be handled carefully. Some true bugs can pierce skin defensively when trapped or roughly handled, and predatory stink bug species have mouthparts designed for attacking insect prey.
Avoid handling unfamiliar bugs with bare fingers.
Baby Stink Bugs vs Bed Bugs
Young stink bugs may occasionally be confused with bed bugs because both can be small, flattened, and brownish.
However, their lifestyles are completely different.
Baby Stink Bug
Baby stink bugs typically have:
- Longer antennae and legs
- Plant-associated behavior
- Variable green, red, black, or brown coloring
- Developing shield-like body
- No interest in feeding on human blood
Bed Bug
Bed bug nymphs generally have:
- Broad, flattened bodies
- Pale or translucent coloration when newly hatched
- Reddish appearance after feeding
- Strong association with beds and sleeping areas
- Blood-feeding behavior
If unexplained bites occur around a bed, stink bugs are unlikely to be responsible.
Baby Stink Bugs vs Ladybugs
Ladybugs are not baby stink bugs.
Ladybugs belong to the beetle family Coccinellidae and undergo complete metamorphosis, including a larval and pupal stage.
Young ladybug larvae look elongated and somewhat alligator-like rather than round like stink bug nymphs.
Adult ladybugs have hardened wing covers and are usually rounded or dome-shaped.
A small red-and-black insect on a leaf therefore is not necessarily a young stink bug; body structure is more useful than color alone.
Are Boxelder Bugs Baby Stink Bugs?
No. Boxelder bugs are a separate type of true bug.
Adult boxelder bugs are usually black with distinctive red or orange lines, while their young nymphs can be bright red.
Because young boxelder bugs often gather in large groups, they may sometimes be mistaken for baby stink bugs.
However, boxelder bugs typically have more elongated bodies than stink bugs and are commonly associated with boxelder and maple trees.
How to Get Rid of Baby Stink Bugs in the Garden
A few stink bugs may not require aggressive treatment. When numbers become large enough to damage vegetables or fruit, early control can reduce the population before nymphs mature.
Simple Control Methods
Try:
- Inspecting the undersides of leaves
- Removing egg masses
- Hand-picking nymphs
- Dropping bugs into soapy water
- Removing heavily infested plant debris
- Controlling weeds around crops
- Using row covers when appropriate
- Monitoring fruit and vegetable plants regularly
Hand-picking and knocking stink bugs into soapy water are recommended options for smaller garden infestations.
Avoid automatically applying broad-spectrum pesticides, since these can also kill pollinators and beneficial predatory insects.
How to Keep Stink Bugs Out of the House
Indoor prevention mainly concerns adult stink bugs looking for overwintering shelter rather than baby stink bugs.
Seal Common Entry Points
Before fall:
- Caulk cracks around windows
- Install weather stripping
- Repair window screens
- Seal gaps around pipes
- Check siding
- Screen vents
- Seal openings around doors
If stink bugs are already indoors, vacuuming or gently collecting them is often simpler than spraying indoor living areas.
FAQs
What do baby stink bugs look like?
They are small, wingless, round-to-oval insects with six legs and long antennae. Depending on species and age, they can be black, red, orange, green, brown, or multicolored.
Are baby stink bugs green?
Some species and developmental stages can be green. Other stink bug nymphs may be red, black, orange, brown, or patterned.
Can baby stink bugs fly?
No. Nymphs lack fully developed functional wings. They become capable of flight only after completing their final molt into adults.
Why are baby stink bugs on my plants?
Plant-feeding stink bugs lay their eggs on vegetation, and the nymphs remain nearby after hatching. They later feed on plant juices, fruits, seeds, and other plant tissues.
Do baby stink bugs turn into adult stink bugs?
Yes. They pass through several nymphal stages, or instars, becoming larger after each molt until the final molt produces a fully winged adult.