A baby praying mantis, called a nymph, looks like a tiny version of the adult but without wings. Dozens to hundreds of them emerge from a single foam-like egg case, each one smaller than a grain of rice, and they’re ready to hunt from the moment they hatch. Whether you’ve found nymphs in your garden or you’re thinking about raising them, here’s what to know about these surprisingly fierce little insects.
What Baby Praying Mantises Look Like
Freshly hatched nymphs are typically only a few millimeters long. They have the same triangular head, oversized eyes, and raptorial front legs as adults, just in miniature. Most species emerge a pale tan or light brown color, though some darken or develop green tones as they grow. They lack wings entirely. Wing buds start appearing in later growth stages and only become fully functional once the mantis reaches adulthood.
Because they’re so small, nymphs are sometimes mistaken for ants or tiny grasshoppers. The easiest giveaway is their posture: even at this size, they hold their front legs folded in the characteristic “praying” position and swivel their heads to track movement, something very few other insects can do.
How They Hatch
Female mantises lay their eggs inside a hardened foam structure called an ootheca, which looks like a lumpy, tan blob roughly the size of a walnut (depending on species). Each ootheca contains anywhere from 50 to 200 individual eggs. In temperate climates, the egg case overwinters outdoors and hatches in late winter to spring when temperatures rise consistently.
Warm weather triggers hatching. Nymphs need at least 10 to 15 consecutive days of warm temperatures, ideally 75 to 80°F with humidity above 50%, before they’ll emerge. In controlled indoor conditions at temperatures above 70°F, hatching can occur in as little as 2 to 6 weeks. In cooler or fluctuating outdoor conditions, it can take months. When they do emerge, all the nymphs spill out within minutes to hours, dangling from silk-like threads before dispersing.
Growth Stages and Molting
Mantis nymphs grow through a series of stages called instars, shedding their exoskeleton each time. Most species go through 6 to 9 molts before reaching adulthood, with each molt producing a noticeably larger nymph. The time between molts is roughly 9 to 15 days, though this varies with temperature and food availability. Warmer conditions and regular feeding speed the process up.
Molting is the most dangerous part of a young mantis’s life. The nymph hangs upside down from a branch or the top of its enclosure, using gravity to slide out of its old skin. Its new exoskeleton is soft and pale, leaving it completely defenseless for up to 48 hours while it hardens. If the environment is too dry, the old exoskeleton can stick and trap the nymph partway through the molt, causing deformities or death.
You’ll know a molt is coming when the nymph stops eating for a day or two and becomes less active. During and after the molt, don’t handle the mantis or leave live feeder insects in the enclosure. A cricket or roach can injure or kill a soft, freshly molted nymph that can’t defend itself.
What to Feed Them
Baby mantises are predators from day one. The standard first food is flightless fruit flies, which are small enough for even the tiniest nymphs to grab and eat. A single fruit fly every 2 to 3 days is sufficient for the earliest instars. As the nymph grows, you can increase both prey size and frequency.
The general rule for prey size: choose insects no larger than the mantis’s abdomen, or roughly half its body length. As nymphs reach mid-stage instars, good options include:
- Pinhead crickets, which are newly hatched crickets small enough for young nymphs
- Small red runner roaches, which come in a range of sizes suitable for nearly every instar
- Green or blue bottle flies, a favorite for mid-sized nymphs
- Wax worms or wax moths, offered occasionally as a higher-fat food source
Nymphs are ambush hunters, so they need to see their prey moving. Dead or stationary food will usually be ignored. If a nymph repeatedly refuses food, it’s likely preparing to molt rather than sick.
Housing a Baby Mantis
Nymph enclosures don’t need to be large. A 32-ounce deli cup works well for most species through the early instars. It keeps the space small enough that the nymph can easily find its food, which matters when both predator and prey are tiny. The enclosure should be at least twice as tall as the mantis is long, giving it room to hang and molt safely.
Ventilation is critical. Stagnant air promotes mold, which can kill nymphs quickly. Poke or drill small holes in both the lid and near the base of the cup to create cross-ventilation. Line the lid’s interior with a piece of mesh or shelf liner so the nymph has a textured surface to grip when it hangs upside down to molt.
For most common species, aim for temperatures between 68 and 80°F and humidity around 60 to 70%. A light misting of the enclosure walls once a day usually provides enough moisture. Nymphs drink water droplets off surfaces rather than from a dish. Avoid soaking the enclosure, as standing water can drown a small nymph and excess moisture encourages bacterial growth.
Why You Need to Separate Them
Praying mantises are cannibalistic at every life stage, including the first. Nymphs will eat their siblings within hours of hatching if they’re kept together. There’s no grace period and no age at which they “grow out of it.” If you put two mantises in the same container, one of them will eventually become food for the other.
If you’ve hatched an ootheca and want to raise multiple nymphs, each one needs its own enclosure. For those who don’t want to house 100+ individual mantises (understandably), the practical approach is to keep a few in separate containers and release the rest outdoors in a garden where they can disperse naturally. Released nymphs are excellent pest control, feeding on aphids, gnats, and other small garden insects as they grow.
How Long Until They’re Adults
From hatching to adulthood, most mantis species take roughly 3 to 6 months depending on temperature, food supply, and species size. Larger tropical species tend toward the longer end. You’ll know a mantis has reached its final molt when it develops full-length wings (in winged species). Males are typically thinner with longer wings, while females are bulkier with shorter wings relative to their abdomen.
Adult mantises live an additional 3 to 8 months on average, with females generally outliving males. The entire lifespan from egg to death is usually about one year for temperate species, fitting neatly into a single growing season.