Are silkworms good for crested geckos?

Yes, as a soft, highly digestible supplemental feeder. Silkworms are very high in protein, low in fat, and gentle on the gut, which makes them excellent for juveniles and any gecko that struggles with harder prey. Their drawback is keeping: they need mulberry leaves or silkworm chow and have a short shelf life, so they're more of a periodic treat than an everyday staple.

Do silkworms have more calcium than discoid roaches?

Silkworms have a somewhat better mineral balance — their calcium-to-phosphorus ratio is closer to even — but they still benefit from a light calcium dusting. Discoid roaches are more clearly phosphorus-heavy and must be dusted. Neither matches the naturally high calcium of black soldier fly larvae.

Which is easier to keep, discoid roaches or silkworms?

Discoid roaches, by a wide margin. They live for months in a simple bin on fruit and grain, tolerate a cool crested gecko room, and barely smell. Silkworms are fussy — they need a specific mulberry-based diet, careful temperature and cleanliness, and they perish after cocooning. If low effort matters, roaches win.

How often should I feed insects to a crested gecko?

Insects are a supplement to a complete commercial crested gecko diet (CGD), offered once or twice a week. Gut-load and dust them with calcium first, and size them no larger than the space between the gecko's eyes.

Do crested geckos need insects at all?

Not strictly — a complete CGD can sustain them. But live insects like discoid roaches or silkworms add protein and natural hunting enrichment, and they're genuinely valuable for growing juveniles and breeding females.

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Geckos

Discoid Roaches vs. Silkworms for Crested Geckos

By Matt Goren · Updated June 25, 2026

When a crested gecko keeper asks me whether to use discoid roaches or silkworms, I always start by reframing the question. Neither is the main meal — a crested gecko (Correlophus ciliatus) lives primarily on a complete commercial crested gecko diet (CGD), the fruit-and-protein powders like Pangea and Repashy. Insects are a once- or twice-weekly supplement for protein and enrichment. So the real question is which supplemental bug earns its place. Both of these can; they just suit different priorities. Here's how I think about it.

What a crested gecko's diet is built on

In the wild on New Caledonia, cresties eat soft fruit, nectar, and the occasional insect. In captivity that translates to:

Staple CGD three to four times a week — the bulk of nutrition.
Live insects once or twice a week for protein and hunting behavior.
Calcium and D3 dusted on insects to prevent metabolic bone disease.
Misting for hydration; cresties drink droplets off leaves.

One care fact shapes this whole comparison: crested geckos are heat-sensitive, happiest around 72–78°F and stressed by sustained heat above the low 80s. That cool-running room is easy for a discoid colony to live in and harder for fussier feeders. (For the broader picture, see the exotic animal care hub.)

Discoid roaches: the low-effort lean staple

Discoid roaches (Blaberus discoidalis) are the supplemental feeder I reach for most:

Lean protein, roughly 20–23% protein and 5–7% fat — a clean protein boost on top of the CGD without piling on fat.
Soft, low-chitin body that's easy to digest and low-risk for impaction, important for small cresties.
Hydrating, around 65–70% moisture.
Genuinely easy to keep: they live for months in a simple bin, eat cheap fruit and grain, don't climb smooth walls, don't fly, and barely smell.
Size range from tiny nymphs to larger nymphs, so you match the feeder to the gecko.

The honest caveat people get wrong: discoids are phosphorus-heavy like nearly all feeders, so you must dust them with calcium — they do not have the "balanced ratio" the internet keeps repeating. They also cost more than crickets and breed slower than dubia. For a self-sustaining supply, see my discoid breeding playbook; to buy them ready to feed, All Angles Creatures stocks discoid roaches sized for cresties.

Silkworms: the soft, protein-rich treat

Silkworms (Bombyx mori) are a premium soft-bodied feeder, and their strengths are real:

Very high protein — silkworms are one of the more protein-dense feeders by dry weight — with low fat (around 9–10%), an excellent lean profile.
Extremely soft and easy to digest, with almost no tough exoskeleton. This is their standout trait: they're gentle on juveniles, older geckos, and any animal recovering from illness, with very low impaction risk.
A better mineral balance than most feeders, with a calcium-to-phosphorus ratio closer to even — though I'd still give them a light calcium dusting to be safe.
High moisture, which aids hydration.
Calm, slow movement that's accessible to timid or less agile geckos.

Their weakness is husbandry. Silkworms eat only mulberry leaves or a mulberry-based silkworm chow, need careful temperature and cleanliness, have a short shelf life, and die after cocooning. They cost more and are harder to source than roaches. That makes them a fantastic periodic feeder rather than a low-effort everyday one. When you want them, All Angles Creatures carries silkworms.

Head-to-head

Factor	Discoid roach	Silkworm
Protein	High (~20–23%)	Very high
Fat	Low (~5–7%)	Low (~9–10%)
Digestibility	Soft, low chitin	Extremely soft — gentlest
Calcium / Ca:P	Phosphorus-heavy — must dust	Closer to even — still dust lightly
Keeping effort	Easy, long-lived, cool-tolerant	Fussy; mulberry diet; short-lived
Cost & sourcing	Cheaper, widely available	Pricier, harder to source
Best role	Everyday lean staple	Soft, premium periodic treat

How I use both

They complement each other nicely:

Discoid roaches as the regular insect supplement — easy to keep, lean, dusted with calcium every feeding.
Silkworms as a periodic premium treat, especially for hatchlings, breeding females, or a gecko that's been off its food and needs something gentle and tempting.
Gut-load the roaches 24–48 hours ahead; silkworms are already nutrient-rich from their mulberry diet.
Size everything to no larger than the space between the eyes, offered in the evening when cresties are active, and follow reptile supplementation guidance for calcium and D3.

The verdict

If you want one practical everyday feeder, discoid roaches win on keeping effort, cost, and lean protein. If you want the gentlest, most digestible feeder for a delicate or finicky gecko, silkworms win — they're just more work to keep alive. The best crested gecko keepers I know use both: discoids as the reliable base and silkworms as the soft, protein-rich treat, all on top of a complete CGD.

Comparing other crested gecko feeders? See discoid roaches vs. hornworms and the crested gecko feeder debate, or browse the full exotic animal care library.

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