How to Breed Discoid Roaches: A Keeper's Expert Guide

I've bred discoid roaches (Blaberus discoidalis) for years, and they're the most beginner-friendly feeder roach there is: docile, quiet, odorless when kept right, non-climbing, and legal where many roaches aren't. Get a handful of conditions right and the colony runs itself. Here's exactly how I do it.

Start with the right breeding stock

Buy a starter group of healthy adults and sub-adults — 100-200 mixed roaches gets you to self-sustaining within a year. Pick active animals with no injuries or deformities.

• ◆Sexing: Adult females are broader and heavier with rounded abdomens; males are slimmer. Both have wings but fly poorly.
• ◆Ratio: Aim for about 1 male to 3-4 females. Too many males stresses the colony without boosting output.

The breeding enclosure

A 32-66 quart opaque plastic tote is ideal — opaque because discoids are nocturnal and breed better in the dark.

• ◆Ventilation: Cut large screened windows in the lid or upper walls. Real airflow prevents the ammonia and mold that crash colonies. Don't rely on a few drilled holes.
• ◆Surface area: Stack cardboard egg flats vertically. This is their hiding, climbing, and breeding space.
• ◆Substrate: None. Run bare-bottom. Loose substrate holds moisture, grows mold, and harbors grain mites. A bare floor scrapes clean in minutes.

Heat and humidity: the make-or-break factors

Discoids breed on warmth. This is the variable that decides success.

Run a thermostat-controlled heat mat or cable on one side or end of the bin — never the whole floor, and never unregulated (an unthermostatted mat can cook the colony). Room temperature alone gives you a sluggish colony that never takes off. Maintain humidity with light misting or a moist corner; track it with a cheap hygrometer.

Keep the bin dim. No lighting needed — these are nocturnal insects that come out to feed and mate in the dark.

Feeding for fertility

Strong, well-fed roaches breed; hungry ones cannibalize.

• ◆Dry base, always available: roach chow, whole grains, or a high-protein dry feed in a shallow dish.
• ◆Fresh produce, a few times a week: carrot, squash, leafy greens, apple, orange for moisture and vitamins. Pull leftovers within 24-48 hours.
• ◆Hydration: water crystals or a moist sponge — never an open dish (it drowns nymphs).

Avoid going to protein extremes — overly protein-rich diets in a crowded bin push roaches toward cannibalism. Balanced beats maxed-out.

Caring for nymphs

Newly dropped nymphs are pale and translucent, darkening with each molt. They're hardy but need:

• ◆Stable humidity (toward the upper end, 60-70%, helps clean molting).
• ◆Finely available food — they'll feed on the same chow and produce.
• ◆Space. Don't overcrowd; crowding stunts growth.

Nymphs cluster under egg flats, so check there to gauge how production is going. A spread of nymph sizes — newly hatched through near-adult — is your sign the colony is reproducing steadily.

Managing growth and hygiene

• ◆Don't overcrowd. When the bin gets packed, split it into a second identical tote. Crowding slows breeding, stresses roaches, and causes die-offs and odor.
• ◆Clean monthly, gently. Lift the egg flats, scrape frass off the bottom, wipe, replace. Don't sterilize or disturb weekly — discoids breed best left alone. Remove dead adults and rotting food as you spot them.
• ◆Watch ventilation. Poor airflow lets ammonia build from waste and harms the colony.

Troubleshooting

Low breeding rate — almost always temperature. Confirm the warm side is 88-95°F; raise humidity to 50-60%; check diet quality.

Cannibalism — overcrowding plus too little food/water. Add space and egg flats, keep produce and water crystals constantly available.

Sudden die-offs — poor ventilation (ammonia buildup) or contaminated/moldy food. Improve airflow, remove uneaten food within 24 hours, and don't let the bin get wet.

The payoff

Get heat, ventilation, food, and space right and a discoid colony quietly turns scraps into a free, endless feeder supply for years. The slow first few months give way to steady harvests once the generations stack.

Want healthy breeding stock to start? All Angles Creatures carries live discoid roaches from nymphs to mature breeders.

For background on insect development and reptile nutrition, see the University of Florida IFAS Extension and the Merck Veterinary Manual on reptile nutrition.

Building the bin from scratch? See how to start a discoid roach breeding setup and keeping discoid roaches alive: breeder secrets revealed.